CN114587026A

CN114587026A - System control circuit and electron cigarette

Info

Publication number: CN114587026A
Application number: CN202210346851.6A
Authority: CN
Inventors: 宋朋亮; 宋利军
Original assignee: Xi'an Wenxian Semiconductor Technology Co ltd
Current assignee: Xi'an Wenxian Semiconductor Technology Co ltd
Priority date: 2022-03-31
Filing date: 2022-03-31
Publication date: 2022-06-07

Abstract

The application provides a system control circuit applied to an electronic cigarette, which comprises a system control module and a first switch unit, wherein the system control module comprises a battery terminal, a first grounding terminal and a system control unit; the system control module further comprises a branch detection unit, the branch detection unit is used for obtaining a second detection voltage, the second detection voltage is used for representing whether the heating branch is conducted or not, the system control unit comprises a second over-suction protection unit, the second over-suction protection unit is respectively electrically connected with the branch detection unit and the switch control unit, when the second over-suction protection unit judges according to the second detection voltage, when the heating branch is conducted, the second over-suction protection unit starts timing, when the timing duration of the second over-suction protection unit is greater than or equal to the second preset duration, the second over-suction protection unit is controlled by the switch control unit, and the first switch unit is kept disconnected. The application also provides an electronic cigarette.

Description

System control circuit and electron cigarette

Technical Field

The application relates to the technical field of electronic cigarettes, in particular to a system control circuit and an electronic cigarette.

Background

The existing electronic cigarette comprises a battery and an atomization component. Referring to fig. 1, the atomizing assembly is electrically connected to a battery, the battery is used for providing electric energy to the atomizing assembly, the atomizing assembly generally includes a system control module, an atomizing core, a first switch unit 910, an airflow sensor 940, and the like, the system control module is correspondingly electrically connected to the battery through a battery terminal B1 and a ground terminal, the atomizing core includes a heating wire 950, the heating wire 950 is electrically connected to the battery through the first switch unit 910, the first switch unit 910 and the airflow sensor 940 are respectively electrically connected to the system control module, the heating wire 950 is used for heating the smoke oil to generate smoke through atomization, and the airflow sensor 940 is used for detecting whether airflow flows, for example, airflow flows in an electronic cigarette when a user smokes the electronic cigarette.

When the system control module detects that airflow flows through the airflow sensor 940, the system control module controls the first switch unit 910 to be opened and conducted, so that a loop formed by the heating wire 950 and the battery is conducted, the heating wire 950 generates heat to heat tobacco tar to generate smoke, the smoke is conveyed into the mouth of a user through a suction nozzle of the electronic cigarette, a smoking effect is achieved, when the system control module detects that the user stops smoking through the airflow sensor 940, the system control module controls the first switch unit 910 to be disconnected and cut off, the heating wire 950 is disconnected from the loop formed by the battery, and the heating wire 950 stops heating.

When the time length of a single smoking of a user is long (over-smoking), for example, over 15s and 20s, the airflow sensor 940 is always triggered during smoking, or the airflow sensor 940 is triggered by mistake for a long time during logistics transportation (over-smoking), which causes the working time of the first switch unit 910 to be too long, causes the temperature of the first switch unit 910 to be too high, may exceed the maximum working temperature of the device, for example, the temperature may cause the lifetime or reliability of the first switch unit 910 to be reduced, may cause the short-circuit damage of the first switch unit 910 to be serious, and may cause a chain reaction, for example, damage to a system control module around the first switch unit 910, or the like.

In order to solve the problem of long-time operation of the first switch unit 910, the current solution is that the system control module controls the trigger duration of the airflow sensor 940, and when the trigger duration of the airflow sensor 940 exceeds a preset duration, for example, the preset duration is 5s or 10s, even if the airflow sensor 940 detects that airflow is triggered, the system control module forcibly controls the first switch unit 910 to stop operating, which is beneficial to protecting the first switch unit 910 and its peripheral circuits.

Disclosure of Invention

However, the over-suction protection mechanism is used for indirectly detecting whether the electronic cigarette works, a leak exists, the first switch unit is not suitable for continuous conduction due to airflow in some cases, for example, the first switch unit is continuously conducted due to some hardware faults, or the first switch unit 210 stops working for a short time, heat is not dissipated and works again, so that the temperature rise of the first switch unit 210 is too high, the temperature rise in the electronic cigarette rises, when the temperature rises continuously, the first switch unit 210, the system control module 272 and the like are deteriorated and damaged, and the electronic cigarette can catch fire in a serious case, so that a safety problem is caused.

The technical problem to be solved by the embodiments of the present application is to provide a system control circuit and an electronic cigarette. The first switching unit can be prevented from operating for a long time.

In order to solve the above technical problem, a first aspect of the embodiments of the present application provides a system control circuit applied to an electronic cigarette, including a system control module and a first switch unit, where the system control module includes a battery terminal, a first ground terminal, and a system control unit, where the battery terminal and the first ground terminal are used to be electrically connected to two ends of a battery assembly correspondingly, the system control unit includes a switch control unit, the switch control unit is electrically connected to a control terminal of the first switch unit, and the first switch unit is used to be connected in series with a heating element to form at least part of a heating branch;

the system control module further comprises a branch detection unit, the branch detection unit is used for obtaining a second detection voltage, the second detection voltage is used for representing whether the heating branch is conducted or not, the system control unit comprises a second over-suction protection unit, the second over-suction protection unit is respectively connected with the branch detection unit and the switch control unit, when the second over-suction protection unit judges according to the second detection voltage when the heating branch is conducted, the second over-suction protection unit starts timing, and when the timing duration of the second over-suction protection unit is greater than or equal to the second preset duration, the second over-suction protection unit controls the first switch unit to be kept disconnected through the switch control unit.

Optionally, the branch detection unit includes an atomization end, the atomization end is electrically connected with one end of the first switch unit, the atomization end is further used for being electrically connected with one end of the heating element, and the second detection voltage is determined according to the voltage of the atomization end.

Optionally, the second detection voltage is the voltage of the atomization end, when the second over-suction protection unit determines that the second detection voltage is greater than a preset first reference voltage or less than a preset second reference voltage, the second over-suction protection unit starts timing, and when the timing duration of the second over-suction protection unit is greater than or equal to a second preset duration, the second over-suction protection unit controls the first switch unit to be kept disconnected through the switch control unit.

Optionally, the branch detection unit further includes a current detection unit, the current detection unit is electrically connected to the atomization end, the current detection unit is configured to obtain a third detection voltage proportional to a current flowing through the heating branch, and the second detection voltage is determined according to the third detection voltage.

Optionally, one end of the first switch unit is electrically connected to the battery terminal, and the other end of the first switch unit is electrically connected to the atomization terminal; the second detection voltage is the third detection voltage, the current detection unit comprises a first detection MOS tube, a first detection operational amplifier, a second detection MOS tube and a third detection resistor, wherein, the grid electrode of the first detection MOS tube is electrically connected with the grid electrode of the first switch unit, the source electrode of the first detection MOS tube is electrically connected with the battery end, the drain electrode of the first detection operational amplifier is electrically connected with the same-direction end of the first detection operational amplifier, the reverse end of the first detection operational amplifier is electrically connected with the atomization end, the same-direction end of the first detection operational amplifier is also electrically connected with the source electrode of the second detection MOS tube, the output end of the first detection operational amplifier is electrically connected with the grid electrode of the second detection MOS tube, the drain electrode of the second detection MOS tube is electrically connected with one end of a third detection resistor, the other end of the third detection resistor is connected with the first grounding end, and the third detection voltage is the voltage at the drain electrode of the second detection MOS tube; alternatively, the first and second electrodes may be,

one end of the first switch unit is electrically connected with the first grounding end, and the other end of the first switch unit is electrically connected with the atomization end; the second detection voltage is the third detection voltage, the current detection unit comprises a first detection MOS tube, a first detection operational amplifier, a second detection MOS tube and a third detection resistor, wherein the grid electrode of the first detection MOS tube is electrically connected with the grid electrode of the first switch unit, the drain electrode of the first detection MOS tube is electrically connected with the first grounding end, the source electrode of the first detection operational amplifier is electrically connected with the reverse end of the first detection operational amplifier, the equidirectional end of the first detection operational amplifier is electrically connected with the atomization end, the reverse end of the first detection operational amplifier is also electrically connected with the drain electrode of the second detection MOS tube, the output end of the first detection operational amplifier is electrically connected with the grid electrode of the second detection MOS tube, the source electrode of the second detection MOS tube is electrically connected with one end of a third detection resistor, the other end of the third detection resistor is connected with the battery end, and the third detection voltage is the voltage at the source electrode of the second detection MOS tube.

Optionally, the branch detection unit further includes a voltage division detection unit, the voltage division detection unit is electrically connected to the atomization end, the voltage division detection unit is configured to obtain a divided voltage proportional to a voltage drop of the heating element, and the second detection voltage is determined according to the divided voltage.

Optionally, one end of the first switch unit is electrically connected to the battery terminal, and the other end of the first switch unit is electrically connected to the atomization terminal; the second detection voltage is equal to the divided voltage, the divided voltage detection unit comprises a fourth detection resistor and a fifth detection resistor, one end of the fourth detection resistor is electrically connected with the atomization end, the other end of the fourth detection resistor is electrically connected with one end of the fifth detection resistor, the other end of the fifth detection resistor is electrically connected with the first grounding end, and the divided voltage is the voltage at the connection point of the fourth detection resistor and the fifth detection resistor; alternatively, the first and second electrodes may be,

one end of the first switch unit is electrically connected with the first grounding end, and the other end of the first switch unit is electrically connected with the atomization end; the second detection voltage is equal to the divided voltage, the divided voltage detection unit comprises a fourth detection resistor and a fifth detection resistor, one end of the fourth detection resistor is electrically connected with the battery end, the other end of the fourth detection resistor is electrically connected with one end of the fifth detection resistor, the other end of the fifth detection resistor is electrically connected with the atomization end, and the divided voltage is the voltage at the connection point of the fourth detection resistor and the fifth detection resistor.

Optionally, the branch detection unit includes a control end of the first switch unit, and the second detection voltage is determined according to a voltage of the control end of the first switch unit.

Optionally, the second detection voltage is a voltage of a control end of the first switching unit, when the second over-suction protection unit determines that the second detection voltage is greater than a first reference voltage or less than a second reference voltage, the second over-suction protection unit starts timing, and when a timing duration of the second over-suction protection unit is greater than or equal to a second preset duration, the second over-suction protection unit controls the first switching unit to keep being disconnected through the switching control unit.

Optionally, the branch circuit that generates heat includes series connection's first switch element, heating element and second detection resistor, branch circuit detection unit is including the detection end that generates heat, the detection end that generates heat is used for being connected with the detection tie point electricity, the detection tie point does first switch element with the tie point of second detection resistor perhaps heating element and second detection resistor's tie point, second detection voltage basis the voltage of the detection end that generates heat is confirmed.

Optionally, the second detection voltage is a voltage of the heating detection end, when the second over-suction protection unit determines that the second detection voltage is greater than the first reference voltage or less than the second reference voltage, the second over-suction protection unit starts timing, and when a timing duration of the second over-suction protection unit is greater than or equal to a second preset duration, the second over-suction protection unit controls the first switch unit to keep off through the switch control unit.

Optionally, the second over-suction protection unit includes an over-suction comparison unit and an over-suction logic unit, one input end of the over-suction comparison unit is connected to the second detection voltage, the other input end of the over-suction comparison unit is connected to a preset first reference voltage or a preset second reference voltage, an output end of the over-suction comparison unit is electrically connected to the over-suction logic unit, and the over-suction logic unit is electrically connected to the switch control unit.

Optionally, the over-suck logic unit includes a second timing unit and a second duration control unit, an input end of the second timing unit is electrically connected to the over-suck comparison unit, an output end of the second timing unit is electrically connected to the second duration control unit, when the over-suck comparison unit determines that the second detection voltage is greater than the first reference voltage or less than the second reference voltage, the second timing unit starts timing, when the over-suck comparison unit determines that the second detection voltage is less than the first reference voltage or greater than the second reference voltage, the second timing unit stops timing, and when the second duration control unit determines that the timing duration of the second timing unit is greater than or equal to the second preset duration, the second duration control unit outputs an over-suck protection signal to control the first switch unit to keep being disconnected.

Optionally, the second timing unit includes a first reference frequency generation unit and a second timing subunit; the second timing subunit is electrically connected with the over-suction comparison unit, the second duration control unit and the first reference frequency generation unit respectively, starts timing when the over-suction comparison unit judges that the second detection voltage is greater than a first reference voltage or less than a second reference voltage, and stops timing when the over-suction comparison unit judges that the second detection voltage is less than the first reference voltage or greater than the second reference voltage; alternatively, the first and second electrodes may be,

the second timing unit comprises a second reference frequency generation unit and a second timing subunit; the second reference frequency generation unit is electrically connected with the over-suction comparison unit, the second timing subunit is electrically connected with the second duration control unit and the second reference frequency generation unit respectively, when the over-suction comparison unit judges that the second detection voltage is greater than the first reference voltage or less than the second reference voltage, the second reference frequency generation unit starts to work, and when the over-suction comparison unit judges that the second detection voltage is less than the first reference voltage or greater than the second reference voltage, the second reference frequency generation unit stops working.

Optionally, the over-suck logic unit includes a second timing unit, a second duration control unit, a third timing unit and a third duration control unit, an input end of the second timing unit and an input end of the third timing unit are respectively electrically connected to the over-suck comparison unit, the second timing unit is electrically connected to the second duration control unit, the third timing unit is electrically connected to the third duration control unit, the third duration control unit is electrically connected to the second timing unit, when the over-suck comparison unit determines that the second detection voltage is greater than the first reference voltage or less than the second reference voltage, the second timing unit starts timing, when the over-suck comparison unit determines that the second detection voltage is less than the first reference voltage or greater than the second reference voltage, the third timing unit starts timing, and when the over-suck comparison unit determines that the second detection voltage is greater than the first reference voltage or less than the second reference voltage, the over-suck comparison unit determines that the second detection voltage is greater than the first reference voltage or less than the second reference voltage And when the second time duration control unit judges that the time duration of the second timing unit is greater than or equal to the second preset time duration, the second over-suction protection unit is used for controlling the first switch unit to be kept disconnected.

Optionally, the second timing unit includes a first reference frequency generation unit and a second timing subunit, and the third timing unit includes a third timing subunit; wherein, the second timing subunit is respectively and electrically connected with the over-absorbing comparison unit, the second time length control unit and the first reference frequency generation unit, the third timing subunit is respectively and electrically connected with the over-absorbing comparison unit, the third time length control unit and the first reference frequency generation unit, the third time length control unit is electrically connected with the second timing subunit, the second timing subunit starts timing when the over-absorbing comparison unit judges that the second detection voltage is larger than the first reference voltage or smaller than the second reference voltage, the third timing subunit starts timing when the over-absorbing comparison unit judges that the second detection voltage is smaller than the first reference voltage or larger than the second reference voltage, the third timing subunit stops timing when the over-absorbing comparison unit judges that the second detection voltage is larger than the first reference voltage or smaller than the second reference voltage, when the third time length control unit judges that the timing time length of the third timing subunit is greater than or equal to a third preset time length, a reset signal is output to the second timing subunit so that the second timing unit stops timing and the timing time length is set to zero; alternatively, the first and second electrodes may be,

the second timing unit comprises a second reference frequency generation unit and a second timing subunit, and the third timing unit comprises a third timing subunit; wherein, the second reference frequency generating unit is electrically connected with the over-suction comparing unit, the second timing subunit is respectively electrically connected with the second duration control unit and the second reference frequency generating unit, the third timing subunit is respectively electrically connected with the over-suction comparing unit, the third duration control unit and the second reference frequency generating unit, the third duration control unit is respectively electrically connected with the second timing subunit and the second reference frequency generating unit, when the over-suction comparing unit judges that the second detection voltage is greater than the first reference voltage or less than the second reference voltage, the second reference frequency generating unit starts working, the second timing subunit starts timing, when the over-suction comparing unit judges that the second detection voltage is less than the first reference voltage or greater than the second reference voltage, the third timing subunit starts timing, when the over-suction comparison unit judges that the second detection voltage is greater than the first reference voltage or less than the second reference voltage, the third timing subunit stops timing, and when the third duration control unit judges that the timing duration of the third timing subunit is greater than or equal to a third preset duration, a reset signal is output to the second timing subunit and the second reference frequency generation unit so as to set the timing duration of the second timing unit to zero and stop the second reference frequency generation unit; alternatively, the first and second electrodes may be,

the third preset time period is less than one tenth of the second preset time period.

Optionally, the system control unit includes an airflow detection unit, the airflow detection unit is used for being electrically connected with the airflow detection element, and the airflow detection unit is further electrically connected with the second over-suction protection unit;

when the timing duration of the second over-suction protection unit is greater than or equal to a second preset duration, the second over-suction protection unit is locked to output an over-suction protection signal to the switch control unit so that the first switch unit is kept disconnected, and the airflow detection unit triggers the second over-suction protection unit to unlock through an edge signal so that the second over-suction protection unit outputs a turn-on signal to the switch control unit.

Optionally, the switch control unit includes a logic gate circuit, one input end of the logic gate circuit is electrically connected to the airflow detecting unit, the other input end of the logic gate circuit is electrically connected to the second over-suction protecting unit, when the airflow detecting unit and the second over-suction protecting unit both output turn-on and turn-off signals, the switch control unit controls the first switch unit to operate, and when at least one of the airflow detecting unit and the second over-suction protecting unit outputs turn-off and turn-off signals, the first switch unit stops operating.

Optionally, the second preset time period is adjustable.

Optionally, the second over-suction protection unit includes a first reference frequency generation unit or a second reference frequency generation unit, wherein the first reference frequency generating unit or the second reference frequency generating unit comprises a frequency comparator, a frequency switching unit, a first current source and a frequency capacitance end, the first end of the first current source is electrically connected with the battery end, the second end of the first current source is respectively electrically connected with the first end of the frequency switch unit, one input end of the frequency comparator and the frequency capacitor end, the other input end of the frequency comparator is connected with a preset first frequency reference voltage, the output end of the frequency comparator is electrically connected with the control end of the frequency switch unit, the second end of the frequency switch unit is electrically connected with the first grounding end, the frequency capacitor end is used for being electrically connected with the frequency capacitor, and the second preset duration is used for being in a proportional relation with the capacitance value of the frequency capacitor; alternatively, the first and second electrodes may be,

the logic control unit comprises an over-suction logic unit, and the over-suction logic unit comprises a first reference frequency generation unit or a second reference frequency generation unit; the first reference frequency generation unit or the second reference frequency generation unit comprises a frequency comparator, a frequency operational amplifier, a frequency switch unit, a first current source, a second current source, a frequency capacitor and a frequency resistance end, wherein the first current source comprises a first frequency MOS (metal oxide semiconductor) tube, and the second current source comprises a second frequency MOS tube; wherein, the source of the first frequency MOS tube and the source of the second frequency MOS tube are electrically connected with the battery end, the grid of the first frequency MOS tube is electrically connected with the grid of the second frequency MOS tube and are commonly connected with the output end of the frequency operational amplifier, one input end of the frequency operational amplifier is connected with a preset second frequency reference voltage, the other input end of the frequency operational amplifier is electrically connected with the drain of the second frequency MOS tube, the drain of the second frequency MOS tube is also electrically connected with the frequency resistance end, the drain of the first frequency MOS tube is respectively electrically connected with the first end of the frequency switch unit, one input end of the frequency comparator and the first end of the frequency capacitor, the other input end of the frequency comparator is connected with a preset first frequency reference voltage, the output end of the frequency comparator is electrically connected with the control end of the frequency switch unit, the second end of the frequency switch unit and the second end of the frequency capacitor are both electrically connected with the first grounding end, the frequency resistor end is used for being electrically connected with the frequency resistor, and the second preset duration is used for being in proportional relation with the resistance value of the frequency resistor.

Optionally, the system control module and the first switch unit are located on the same chip, the battery terminal is a battery pin, and the first ground terminal is a first ground pin; alternatively, the first and second electrodes may be,

the system control module is located on the third chip, the first switch unit is located outside the third chip, the battery end is a battery pin, the first grounding end is a first grounding pin, the system control module further comprises a first switch control pin, and the first switch control pin is electrically connected with the control end of the first switch unit.

A second aspect of the embodiments of the present application provides an electronic cigarette, including: a battery assembly including a battery;

the atomization assembly comprises the system control circuit, the atomization assembly further comprises a heating element, a battery end and a first grounding end of the system control circuit are electrically connected with two ends of the battery assembly correspondingly, a first switch unit of the system control circuit is connected with the heating element in series to form at least part of heating branches, the heating branches are connected with the system control module in parallel to form a parallel circuit, and the parallel circuit is electrically connected with the battery assembly.

Optionally, the system control module includes an airflow detection end, the airflow detection end is used for being electrically connected with the airflow detection element, the system control unit includes an airflow detection unit, the system control unit further includes a first over-suction protection unit, the first over-suction protection unit includes a first timing unit and a first time length control unit, the airflow detection unit is electrically connected with the airflow detection end, the first timing unit, the first time length control unit and the switch control unit, and the first time length control unit is electrically connected with the switch control unit and the first timing unit; when the airflow detection unit detects airflow flowing through the airflow detection element, the first timing unit starts timing, the switch control unit drives the first switch unit to work, when the airflow detection unit does not detect airflow flowing through the airflow detection element, the first timing unit stops timing and sets zero, the switch control unit stops driving the first switch unit to stop working, when the timing duration of the first timing unit is greater than or equal to a first preset duration, the first time control unit locks and outputs an over-suction protection signal to the switch control unit so that the first switch unit is kept disconnected, and the airflow detection unit triggers the first time control unit to unlock through an edge signal so that the first over-suction protection unit outputs a turn-on signal to the switch control unit.

Optionally, the first preset time duration is equal to the second preset time duration.

Optionally, the switch control unit drives the first switch unit to operate in a PWM mode or a PFM mode, or the switch control unit drives the first switch unit to operate in a normally open conducting mode.

This application embodiment is worked as through the setting when second protection unit timing length of time is more than or equal to the second and predetermines the length of time, and the second protection unit passes through the control of on-off control unit first switch unit keeps the disconnection, and when the disconnection of second switch unit back, the branch circuit disconnection that generates heat to heating element can not produce heat again, first switch unit and peripheral temperature can not rise again, can prevent that first switch unit or system control module etc. from arousing the electron cigarette damage because high temperature damages, especially can not take place the conflagration. Moreover, this embodiment is through whether the direct detection branch road that generates heat switches on, and the indirect detection mode in the background art relatively detects more accurately. Moreover, this embodiment is whether the branch that generates heat is directly listened and is switched on, no matter the air current reason causes the branch that generates heat to switch on, or causes the branch that generates heat to switch on by non-air current reason, this application homoenergetic is suitable for, and application scope is wide.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a circuit block diagram of a prior art atomizing assembly;

figure 2 is a block diagram of the electronic cigarette according to the first embodiment of the present application;

FIG. 3a is a partial block diagram of a system control circuit of the first embodiment;

FIG. 3b is a schematic diagram of the connection of the over-suction protection unit and the over-suction logic unit in the first embodiment;

FIG. 3c is a schematic diagram of the connection of an over-suction protection unit and an over-suction logic unit in another embodiment of the present application;

FIG. 3d is a block diagram of a first reference frequency generating unit or a second reference frequency generating unit according to an embodiment of the present application;

FIG. 3e is a circuit block diagram of a first reference frequency generating unit or a second reference frequency generating unit according to another embodiment of the present application;

figure 4 is a block diagram of the electronic cigarette according to another embodiment of the present application;

figure 5 is a block diagram of the electronic cigarette according to a second embodiment of the present application;

figure 6 is a block diagram of the electronic cigarette according to another embodiment of the present application;

figure 7a is a block diagram of the electronic cigarette according to the third embodiment of the present application;

FIG. 7b is a block diagram of a portion of a control circuit of a system according to a third embodiment of the present application;

figure 7c is a block diagram of the electronic cigarette according to another embodiment of the present application;

figure 7d is a block diagram of the electronic cigarette according to yet another embodiment of the present application;

figure 7e is a block diagram of the electronic cigarette according to yet another embodiment of the present application;

FIG. 8 is a schematic diagram of the connection of an over-suction protection unit and an over-suction logic unit in a fourth embodiment of the present application;

FIG. 9 is a schematic diagram of the connection of an over-suction protection unit and an over-suction logic unit in another embodiment of the present application;

FIG. 10 is a block diagram of a portion of a control circuit of a system according to a fifth embodiment of the present application;

FIG. 11 is a block diagram of a portion of a control circuit of a system according to a sixth embodiment of the present application;

FIG. 12 is a block diagram of a portion of a system control circuit according to a seventh embodiment of the present application;

FIG. 13a is a block diagram of a portion of a system control circuit according to an eighth embodiment of the present application;

fig. 13b is a circuit block diagram of the first protection unit, the second protection unit, the airflow detection unit, the switch control unit, and the first switch unit according to the eighth embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The terms "comprising" and "having," and any variations thereof, as appearing in the specification, claims and drawings of this application, are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or modules is not limited to the listed steps or elements but may alternatively include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus. Furthermore, the terms "first," "second," and "third," etc. are used to distinguish between different objects and are not used to describe a particular order. The electrical connection includes a direct electrical connection and an indirect electrical connection, and the indirect electrical connection means that other electronic components, pins and the like can exist between two electrically connected components. The terminal XX referred to in this application may or may not be an actual terminal, such as only one terminal of a component or one terminal of a wire. Three cases are mentioned and/or included in the present application, for example, a and/or B, including A, B, A and B.

Referring to fig. 2, the present application provides an electronic cigarette, which includes a battery assembly 100 and an atomization assembly 200. The battery assembly 100 includes a battery 110 (bare cell 110) and a battery protection circuit 120, and the battery 110 and the battery protection circuit 120 are generally wrapped together to supply power to the outside. In addition, in other embodiments of the present application, the battery assembly 100 may not include a battery protection circuit. The atomization assembly 200 is electrically connected with the battery assembly 100, the battery assembly 100 is used for supplying power to the atomization assembly 200, the atomization assembly 200 generally comprises a system control circuit, an atomization core, an airflow detection element 240 and the like, the system control circuit is electrically connected with the battery assembly 100, the atomization core comprises a heating element 250, the heating element 250 and the airflow detection element 240 are respectively electrically connected with the system control circuit, the heating element 250 is used for heating the tobacco tar to atomize and generate smoke, and the airflow detection element 240 is used for detecting whether airflow flows in the electronic cigarette.

In an embodiment of the present application, the battery 110 is a rechargeable battery 110 such as a lithium battery 110, and may also be a non-rechargeable battery 110. In this application, the battery protection circuit 120 includes a battery protection module 130, the battery protection module 130 is electrically connected to the battery 110, a first resistor R1 and a first capacitor C1 are further disposed between the battery 110 and the battery protection module 130, and the first resistor R1 and the first capacitor C1 are used for voltage stabilization filtering. In addition, in other embodiments of the present application, the first resistor R1 and the first capacitor C1 may not be provided between the battery 110 and the battery protection module 130, or only one of them may be provided, and other circuits or electronic components may be provided.

In the present application, the battery protection module 130 is used to protect the battery 110 and prevent permanent damage to the battery 110 itself in the case of overdischarge, discharge overcurrent, and the like of the battery 110. In this application, the battery protection module 130 includes a power supply terminal VDD, a second ground terminal GND2, an over-discharge voltage protection unit, a discharge over-current protection unit, a system terminal VM, a first reference voltage generation unit, a logic control unit, and the like, wherein the power supply terminal VDD and the second ground terminal GND2 are electrically connected to the positive electrode and the negative electrode of the battery 110, so that the battery 110 can supply power to the battery protection module 130. The system side VM is used to monitor the real-time current flowing through the atomizing assembly 200, although the system side VM may have other functions.

In the present application, the first reference voltage generating unit provides a reference voltage to the over-discharge voltage protection unit, the discharge over-current protection unit, and the like to determine whether the battery 110 is in an over-discharge voltage state, an over-discharge current state, and the like. The over-discharge voltage protection unit is used for protecting the battery 110 when detecting that the voltage of the battery 110 is lower than the reference voltage provided by the first reference voltage generation unit during the discharging process of the battery 110, for example, controlling the battery 110 to perform only the minimum discharging, and generally stopping the power supply to the atomizing assembly 200, so as to prevent the battery 110 from being permanently damaged due to the over-discharge of the battery 110. The logic control unit is used for controlling the working state and control logic of each module of the battery protection circuit 120, controlling whether the battery 110 discharges outwards, and controlling whether the battery 110 charges.

In an embodiment of the present application, the electronic cigarette has a charging function, and the battery protection module 130 may further include an overcharge voltage protection unit and a charge overcurrent protection unit. In addition, in another embodiment of the present application, the electronic cigarette may not have a charging function, and at this time, charging protection is not required. In addition, in this embodiment, the battery protection module 130 further includes a short-circuit protection unit, a temperature protection unit, and a reference frequency generation unit.

In this application, the battery protection circuit 120 further includes a second switch unit 140, a first end of the second switch unit 140 is connected to a negative electrode of the battery or a positive electrode of the battery, a second end of the second switch unit 140 is electrically connected to the atomizing assembly, and a second end of the second switch unit 140 is further electrically connected to the system terminal VM.

In one embodiment of the present application, the atomizing core of the atomizing assembly 200 generally includes two types: ceramic atomizing core and cotton atomizing core. The ceramic atomization core comprises a ceramic seat and a heating element 250, the heating element 250 is installed on the ceramic seat or in the ceramic seat, the ceramic seat is communicated with the tobacco tar bin to supplement the tobacco tar in the tobacco tar bin to the ceramic seat, and when the heating element 250 heats, the ceramic seat is conducted with heat, so that the tobacco tar atomization is realized by heating the tobacco tar. The cotton atomizing core includes oil guide cotton, heating element 250, and oil guide cotton is located heating element 250, and oil guide cotton and tobacco tar storehouse intercommunication are on supplementing the oil guide cotton with the tobacco tar in the tobacco tar storehouse, and when heating element 250 heated, oil guide cotton that is located heating element 250 was heated, and the tobacco tar that oil guide cotton absorbed is heated and is realized the tobacco tar atomizing. The heating element 250 is generally a heating wire or a heating wire, and the material of the heating wire or the heating wire is, for example, iron-chromium-aluminum, stainless steel, nickel-chromium alloy, pure nickel, pure titanium, or the like. The present application is not limited to the two atomizing cores described above, but other conventional atomizing cores may also be used by those skilled in the art.

With reference to fig. 2, in an embodiment of the present disclosure, the system control circuit includes a system control module 272 and a first switch unit 210, and the system control module 272 includes a battery terminal BAT1, a first ground terminal GND1, an atomization terminal AT, an airflow detection terminal EN, and a system control unit 220. The battery terminal BAT1 and the first ground terminal GND1 are electrically connected to the battery assembly 100, respectively; the atomization end AT is electrically connected with the heating element 250; the airflow detecting terminal EN is electrically connected to the airflow detecting element 240, and the airflow detecting element 240 is, for example, an airflow sensor, such as a capacitive microphone, a switch microphone, or the like. In the present embodiment, the system control unit 220 is electrically connected to the battery terminal BAT1, the first ground terminal GND1, the control terminal of the first switch unit 210, and the atomization terminal AT, respectively.

In the present application, the first switching unit 210 and the heating element 250 are connected in series to form a heating branch, and the battery 110, the second switching unit 140, the heating branch and the system control module 272 are electrically connected to form a discharging main loop, wherein the battery 110 and the second switching unit 140 are connected in series, the heating branch and the system control module 272 are connected in parallel to form a parallel circuit, and the parallel circuit is connected in series with the battery 110 and the second switching unit 140 to form a discharging main loop.

In the present application, the first switch unit 210 and the system control module 272 are generally arranged in the following four ways, but those skilled in the art can also simply modify the circuit described below as needed, and this is within the scope of the present application.

1. Referring to fig. 2, the first switch unit 210 and the system control module 272 are located on the same chip (the first switch unit 210 is built in), which may be referred to as an atomization control chip, a first end of the first switch unit 210 is electrically connected to the battery terminal BAT1 (the first switch unit 210 is disposed on the top), a second end of the first switch unit 210 is electrically connected to the atomization end AT, the atomization end AT is electrically connected to one end of the heating element 250, the other end of the heating element 250 is electrically connected to the first ground terminal GND1, and a control end of the first switch unit 210 is electrically connected to the system control unit 220. In this embodiment, the system control unit 220 controls the first switch unit 210 to be turned on or off, so that when the system control unit 220 controls the first switch unit 210 to be turned on, the heating branch is turned on and the heating element 250 generates heat, and when the system control unit 220 controls the first switch unit 210 to be turned off and turned off, the first switch unit 210 keeps stopping working, the heating branch is turned off and the heating element 250 stops generating heat. When the system control module 272 is located on the chip, the battery terminal BAT1 is the battery 110 pin, the first ground terminal GND1 is the first ground pin, the atomization terminal AT is the atomization pin, and the airflow detection terminal EN is the airflow detection pin.

2. Referring to fig. 4, the first switch unit 210 and the system control module 272 are not located on the same chip (the first switch unit 210 is external, and the system control module 272 is located on a third chip), the first end of the first switch unit 210 is electrically connected to the battery terminal BAT1 (the first switch unit 210 is upper), the second end of the first switch unit 210 is electrically connected to the atomization terminal AT, the atomization terminal AT is electrically connected to one end of the heating element 250, the other end of the heating element 250 is electrically connected to the first ground terminal GND1, and the control terminal of the first switch unit 210 is electrically connected to the system control unit 220 through the first switch control terminal GT (pin). In the present embodiment, the system control unit 220 controls the first switch unit 210 to be turned on or off, so that the heat generating element 250 generates heat when the system control unit 220 controls the first switch unit 210 to be turned on, and the heat generating element 250 stops generating heat when the system control unit 220 controls the first switch unit 210 to be turned off. In this embodiment, the first switch unit 210 is located on one chip, the system control module 272 is located on another chip, and the two chips may be packaged together or not. In addition, in other embodiments of the present application, the system control module 272 may not be provided with the fogging end AT (pin), and the second end of the first switch unit 210 is electrically connected to one end of the heating element 250.

3. Referring to fig. 5, the first switch unit 210 and the system control module 272 are located on the same chip (the first switch unit 210 is built in), a first end of the first switch unit 210 is electrically connected to a first ground GND1 (the first switch unit 210 is placed below), a second end of the first switch unit 210 is electrically connected to an atomization end AT, the atomization end AT is used for electrically connecting to one end of the heating element 250, the other end of the heating element 250 is electrically connected to a battery terminal BAT1, and a control end of the first switch unit 210 is electrically connected to the system control unit 220. In the present embodiment, the system control unit 220 controls the first switch unit 210 to be turned on or off, so that the heat generating element 250 generates heat when the system control unit 220 controls the first switch unit 210 to be turned on, and the heat generating element 250 stops generating heat when the system control unit 220 controls the first switch unit 210 to be turned off.

4. Referring to fig. 6, the first switch unit 210 and the system control module 272 are not located on the same chip (the first switch unit 210 is external, and the system control module 272 is located on a third chip), a first end of the first switch unit 210 is electrically connected to the first ground GND1 (the first switch unit 210 is down), a second end of the first switch unit 210 is electrically connected to the atomization end AT, the atomization end AT is electrically connected to one end of the heating element 250, the other end of the heating element 250 is electrically connected to the battery terminal BAT1, and a control end of the first switch unit 210 is electrically connected to the system control unit 220 through the first switch control end GT (pin). In the present embodiment, the system control unit 220 controls the first switch unit 210 to be turned on or off, so that the heat generating element 250 generates heat when the system control unit 220 controls the first switch unit 210 to be turned on, and the heat generating element 250 stops generating heat when the system control unit 220 controls the first switch unit 210 to be turned off. In this embodiment, the first switch unit 210 is located on one chip, the system control module 272 is located on another chip, and the two chips may be packaged together or not. In addition, in other embodiments of the present application, the system control module 272 may not be provided with the fogging end AT (pin), and the second end of the first switch unit 210 is electrically connected to one end of the heating element 250.

In the present application, the first switch unit 210 includes an NMOS transistor or a PMOS transistor, and the first switch unit 210 is exemplified as a PMOS transistor in the present embodiment. When the system control unit 220 detects that no airflow flows through the airflow detecting element 240 (for example, the user does not smoke), the system control unit 220 stops driving the first switching unit 210 to stop working, and at this time, the first switching unit 210 is turned off, the heating branch is turned off, and the heating element 250 does not heat. When the system control unit 220 detects that airflow flows (for example, a user smokes) through the airflow detecting element 240, the system control unit 220 drives the first switch unit 210 to operate, so that the heating element 250 continuously heats or intermittently heats to heat the tobacco tar to generate smoke, and the smoke is delivered to the mouth of the user through the suction nozzle, thereby achieving a smoking effect.

The conventional system control unit 220 generally drives the heat generating unit to heat, but is not limited to the following three driving methods, and may be other conventional driving methods.

1. The system control unit 220 drives the heating element 250 to work through a PWM (pulse width modulation) mode, specifically, drives the first switch unit 210 to work in a PWM mode, where the PWM mode is a mode in which the frequency (period) is not changed, and the on-time and the off-time of the first switch unit 210 are adjustable, and in this way, the first switch unit 210 is turned on during the on-time in one period, and the first switch unit 210 is turned off during the off-time. The driving method can realize constant power and constant voltage output of the electronic cigarette, when the electronic cigarette does not work (for example, when the electronic cigarette does not smoke), the system control unit 220 stops driving the first switch unit 210, the first switch unit 210 is kept normally off, and the first switch unit 210 does not work at this time.

2. The system control unit 220 drives the heating element 250 to work in a PFM (pulse frequency modulation) mode, specifically, drives the first switch unit 210 to work in a PFM mode, where the PFM mode is a mode in which the frequency (period) can be adjusted, and the on-time or off-time of the first switch unit 210 is unchanged, such that the first switch unit 210 is turned on at the on-time in one period, and the first switch unit 210 is turned off at the off-time. The driving method can realize constant power and constant voltage output of the electronic cigarette, when the electronic cigarette does not work (for example, when the electronic cigarette does not smoke), the system control unit 220 stops driving the first switch unit 210, the first switch unit 210 is kept normally off, and the first switch unit 210 does not work at this time.

3. The system control unit 220 drives the first switch unit 210 to operate in a normally on/off manner, specifically, when it is detected that a user smokes, the airflow detection element 240 is always triggered during a smoking time period, and the first switch unit 210 is always on/off during the triggered time period, so that the first switch unit 210 is not turned off/off. When the electronic cigarette does not work (for example, when the electronic cigarette does not smoke), the system control unit 220 stops driving the first switch unit 210 at this time, the first switch unit 210 is turned off, and at this time, the first switch unit 210 does not work.

In the present application, a person skilled in the art may further add an indicating element, a motor, and the like as needed, where the indicating element is, for example, an LED lamp, a display screen, and the like, and the indicating element, the motor, and the like are electrically connected to the system control module 272, respectively. In addition, when the electronic cigarette has a charging function, the system control module 272 is electrically connected to the charging interface 260 through a charging terminal (pin) VCC at this time, the system control module 272 includes a charging unit 230, the charging unit 230 is electrically connected to the system control unit 220, the battery terminal BAT1 and the charging interface 260, respectively, and the charging unit 230 is configured to control a charging process and is configured to provide a charging voltage and a charging current that conform to a charging curve of the battery 110.

When the user takes a cigarette for a long time (over-smoking), for example, over 15s and 20s, the airflow detecting element 240 is triggered during smoking, or the electronic cigarette is in logistics transportation, the airflow detecting element 240 is triggered by mistake for a long time (over-smoking); the first switch unit 210 may operate for a long time, which may cause the temperature of the first switch unit 210 to rise too high, and may exceed the maximum operating temperature of the device, for example, 150 ℃, which may cause the lifetime or reliability of the first switch unit 210 to decrease, which may cause short-circuit damage to the first switch unit 210, or temperature rise, which may cause a chain reaction, for example, damage to the system control module 272 around the first switch unit 210.

In order to solve the above problem, in the present application, the system control unit 220 includes an airflow detecting unit 281, a first timing unit, and a switch control unit 284 (see fig. 3a), when the airflow detecting unit 281 detects that the airflow flows greatly through the airflow detecting element 240, for example, the airflow detecting unit 281 detects whether the airflow, the airflow is small or large by detecting the microphone switch conduction, the microphone capacitance change, the frequency change of the microphone capacitance, and the like, when the airflow detecting unit 281 judges that the airflow flows or the airflow flows greatly, the first timing unit performs timing, and the switch control unit 284 drives the first switch unit 210 to operate through the above method, and the heating element 250 heats up, so as to achieve the smoke atomization effect. When the airflow detecting unit 281 detects that the airflow flow is small or no airflow flow through the airflow detecting element 240, the first timing unit stops timing, and the switch control unit 284 stops driving the first switching unit 210, and the first switching unit 210 remains off. When the airflow detecting unit 281 detects that the airflow holding time is long through the airflow detecting element 240, and when the time length counted by the first timing unit is greater than or equal to the first preset time length, the system control unit 220 also forcibly stops driving the first switch unit 210, and the first switch unit 210 keeps off, so that the first switch unit 210 can be prevented from being over-heated. In the present application, the first preset time period ranges from 4s to 15s, for example, 4s, 5s, 6s, 7s, 8s, 9s, 10s, 11s, 12s, 13s, 14s, 15s, and the like.

However, the over-suction protection mechanism is to indirectly detect whether the electronic cigarette works, and a leak exists, and in some cases, the first switch unit is not suitable for continuous conduction due to airflow, for example, the first switch unit is continuously conducted due to some hardware faults, or the first switch unit 210 stops working for a short time, and heat is not dissipated and works again, so that the temperature rise of the first switch unit 210 is too high, and further the temperature rise inside the electronic cigarette rises, when the temperature rises continuously, the first switch unit 210, the system control module 272 and the like may be deteriorated and damaged, and the electronic cigarette may catch fire in a serious case, which causes a safety problem.

First embodiment

Referring to fig. 2, in the present embodiment, the first switch unit 210 is disposed on the first switch unit 210, that is, the first end of the first switch unit 210 is electrically connected to the battery terminal BAT1, the battery terminal BAT1 is electrically connected to the positive electrode of the battery 110, or is electrically connected to the positive electrode of the battery 110 via the second switch unit 140, the second end of the first switch unit 210 is electrically connected to the atomization end AT, the atomization end AT is electrically connected to one end of the heating element 250, the other end of the heating element 250 is connected to the first ground GND1, the first ground GND1 is electrically connected to the negative electrode of the battery 110 via the second switch unit 140, or is electrically connected to the negative electrode of the battery 110, and the atomization end AT is a connection point (hereinafter referred to as an atomization connection point) between the first switch unit 210 and the heating element 250. In addition, in other embodiments of the present application, please refer to fig. 4, the first switch unit 210 is disposed on the upper portion and the first switch unit 210 is disposed on the outer portion, and the atomization end AT is electrically connected to the atomization connection point.

In this embodiment, when the first switch unit 210 is turned on, the heating branch has a larger current flowing, generally AT an ampere level, such as 0.5A, 1A, 2A, etc., a voltage of a connection point (an atomization connection point) between the first switch unit 210 and the heating element 250 is a voltage of the battery terminal BAT1 minus a voltage drop of the first switch unit 210, a voltage of the battery terminal BAT1 is a voltage of the battery 110 or a voltage of the system terminal VM, voltage drops of the first switch unit 210 and the second switch unit 140 are generally AT a millivolt level, a voltage of the atomization connection point is generally greater than 3.2V, and a voltage of the atomization terminal AT is larger and is AT a high level; when the first switch unit 210 is turned off, the heating branch is turned off, no current flows in the heating branch, the voltage AT the connection point between the first switch unit 210 and the heating element 250 is the voltage of the first ground GND1, the voltage of the atomization end AT relative to the first ground GND1 is 0, the voltage is low level, the voltage of the first ground GND1 is 0 or the voltage of the system end VM, the voltage drop of the second switch unit 140 is generally in microvolt level, generally in 0 or microvolt level (the current on the second switch unit 140 is in microvolt level), the voltage AT the atomization connection point is generally less than 0.5V, and the voltage of the atomization end AT is small. Therefore, whether the heating branch is turned on or off can be determined by determining the voltage at the connection point of the first switching unit 210 and the heating element 250, and further, whether the heating element 250 is heating is determined by determining whether the first switching unit 210 is turned on or off.

Referring to fig. 3a, in the present embodiment, the system control unit 220 includes an airflow detecting unit 221 and a switch control unit 224. The airflow detecting unit 221 is electrically connected to the airflow detecting element 240, the airflow detecting unit 221 is electrically connected to the switch control unit 224, and the switch control unit 224 is electrically connected to the control terminal of the first switch unit 210. When the airflow detecting element 240 detects that there is a change caused by airflow flowing, the airflow detecting unit 221 may detect the change and output an on/off signal to the switch control unit, and when the airflow detecting element 240 does not detect that there is airflow flowing, the airflow detecting unit 221 defaults to output an off/off signal to the switch control unit.

In this embodiment, the system control module 272 further includes a branch detection unit, where the branch detection unit is configured to obtain a second detection voltage, and the second detection voltage is used to indicate whether the heating branch is turned on. In this embodiment, the branch detecting unit includes an atomization end AT, and a voltage of the atomization end AT is used to determine the second detection voltage. In this embodiment, the voltage of the atomization end AT is the second detection voltage, but in other embodiments, the voltage of the atomization end AT may be converted to obtain the second detection voltage. In this embodiment, the system control module 272 can determine whether the heating branch is turned on by the voltage of the atomization terminal AT, and further determine whether the heating element 250 is heating.

In this embodiment, the system control unit 220 further includes an over-suction protection unit 223, the over-suction protection unit 223 is electrically connected to the branch detection unit and the switch control unit 224, in this embodiment, the atomization end AT, and the over-suction protection unit 223 can determine whether the heating element 250 is heating by detecting the voltage of the atomization end AT. The overdraw protection unit 223 outputs a turn-on signal to the switch control unit 224 under normal conditions.

Referring to fig. 3a and fig. 3b, in the present embodiment, the over-suction protection unit 223 includes an over-suction comparison unit 410, the over-suction comparison unit 410 is, for example, a voltage comparator, one input terminal of the over-suction comparison unit 410 is electrically connected to the branch detection unit, in the present embodiment, the atomization terminal AT, the other input terminal of the over-suction comparison unit 410 is electrically connected to a third reference voltage generation unit, and the third reference voltage generation unit generates a first reference voltage Vref1 and inputs the first reference voltage Vref1 to the over-suction comparison unit 410, in the present embodiment, the first reference voltage Vref1 is generally between 0.5V and 3.2V, for example, 0.5V, 1V, 1.5V, 2V, 2.5V, 3V, 3.2V, and the like.

In this embodiment, when the first switching unit 210 is turned off, the heat generating branch is turned off AT this time, no current flows, the voltage of the atomization end AT is equal to the voltage of the first ground end GND1, the voltage of the first ground end GND1 is 0 or microvoltage (the voltage drop of the second switching unit 140 is microvoltage), and is less than the first reference voltage Vref1, and the over-absorption comparing unit 410 outputs a second level signal; when the first switch unit 210 is turned on, the heating branch is turned on, a large current flows through the heating branch AT an ampere level, the voltage of the atomization end AT is similar to the voltage of the battery end BAT1, the voltage of the battery end BAT1 is generally greater than 3.2V and greater than the first reference voltage Vref1, and the overdraw comparison unit 410 outputs a first level signal.

In this embodiment, the over-suction protection unit 223 further includes an over-suction logic unit, the over-suction logic unit is electrically connected to the over-suction comparison unit 410, and the over-suction logic unit is further electrically connected to the switch control unit 224.

Referring to fig. 3a and fig. 3b in combination, in the present embodiment, the overdriving logic unit includes a second timing unit 420 and a second duration control unit 430, an input end of the second timing unit 420 is electrically connected to an output end of the overdriving comparison unit 410, an output end of the second timing unit 420 is electrically connected to the second duration control unit 430, and an output end of the second duration control unit 430 is electrically connected to the switch control unit 224. In addition, in order to maintain the signal at the output end of the second duration control unit 430, the overdriving logic unit may further include a flip-flop, an input end of the flip-flop is electrically connected to the output end of the second duration control unit 430, an output end of the flip-flop is electrically connected to the switch control unit 224, or the flip-flop is not provided.

In this embodiment, when an air flow flows, the air flow detecting unit 221 is triggered, the first switching unit 210 is turned on and turned on, the over-suction comparing unit 410 determines that the voltage of the atomization end AT is greater than the first reference voltage Vref1, AT this time, the over-suction comparing unit 410 outputs a first level signal, the second timing unit 420 starts timing (edge triggering or level triggering), when no air flow flows (or is AT a low level of the PWM signal or a low level of the PFM signal), the first switching unit 210 is turned off and turned off, the heating branch is not turned on, no current flows on the heating branch, AT this time, the over-suction comparing unit 410 determines that the voltage of the atomization end AT is lower than the first reference voltage Vref1, the over-suction comparing unit 410 outputs a second level signal, the second timing unit 420 stops timing (edge triggering or level triggering) and sets a timing duration of the second timing unit 420 to zero, so that the second timing unit 420 can obtain a heating duration of the heating element 250 in real time and output the heating duration to the second control unit Element 430. In this embodiment, the first level signal is, for example, a high level or a low level, and the second level signal corresponds to, for example, a low level or a high level. The edge trigger is, for example, a rising edge trigger or a falling edge trigger, and the level trigger is, for example, a high level trigger or a low level trigger. In the present embodiment, the second preset time period ranges from 4s to 15s, for example, 4s, 5s, 6s, 7s, 8s, 9s, 10s, 11s, 12s, 13s, 14s, 15s, and so on.

When the first switch unit 210 is not continuously turned on by the airflow or the first switch unit 210 is continuously turned on by the airflow (for example, the third driving method) or the first switch unit 210 is continuously turned on by other reasons, the second timing unit 420 keeps timing all the time without stopping timing and setting zero, the second timing unit 420 outputs the timing duration to the second duration control unit 430 in real time, when the second duration control unit 430 knows that the duration of the first switch unit 210 being turned on is greater than or equal to the second preset duration, the second duration control unit 430 outputs an over-suction protection signal to the switch control unit 224, the switch control unit 224 controls the first switch unit 210 to be turned off, at this time, the first switch unit 210 keeps stopping working, when the first switch unit 210 being turned off, the heating branch is turned off, the heating element 250 is not reheated, and the temperature of the first switch unit 210 and the surrounding temperature thereof is not raised any more, the first switching unit 210 or the system control module 272 and the like can be prevented from being damaged by high temperature, and particularly, the electronic cigarette cannot be damaged by fire; moreover, this embodiment is through whether the direct detection branch road that generates heat switches on, and the indirect detection mode in the background art relatively detects more accurately. Moreover, this embodiment is whether the branch that generates heat is directly listened and is switched on, no matter the air current reason causes the branch that generates heat to switch on, or causes the branch that generates heat to switch on by non-air current reason, and this application homoenergetic is suitable for.

Referring to fig. 2 and fig. 3a, in the embodiment, when the second duration control unit 430 knows that the duration of the conduction of the first switching unit 210 is greater than or equal to the second preset duration, the second duration control unit 430 outputs the over-absorption protection signal to the switching control unit 224, and meanwhile, the second duration control unit 430 locks and outputs the over-absorption protection signal to the switching control unit 224, and controls the timing duration of the second timing unit 420 to be set to zero, which is beneficial to reducing energy consumption. In this embodiment, the over-suction protection signal is, for example, an off-cut signal, or a signal obtained by processing the off-cut signal, as long as the first switching unit 210 can be controlled to be turned off by the switching control unit 224.

In the present embodiment, the switch control unit 224 includes a logic gate circuit, such as an and gate, in which two input terminals of the and gate are respectively and electrically connected to the over-suction protection unit 223 and the air flow detection unit 221, and an output terminal of the and gate is electrically connected to other circuit units in the switch control unit 224. In the present embodiment, only when the over-suction protection unit 223 and the airflow detection unit 221 both output the turn-on signal to the switch control unit 224, the switch control unit 224 controls the first switch unit 210 to turn on, and in a normal case, the over-suction protection unit 223 both outputs the turn-on signal. In addition, in other embodiments of the present application, the logic gate circuit may also be a combination of an and gate and a not gate, a combination of an or gate and a nand gate, an and gate, an or gate, and a not gate to implement the desired signal, the not gate may be located in front of or behind the and gate or the or gate, the number of the not gate, the and gate, or gate may be one or more, and those skilled in the art may set the desired functions according to actual needs.

In this embodiment, when the second duration control unit 430 determines that the timing duration of the second timing unit 420 is greater than or equal to the second preset duration, which indicates that the working time of the first switch unit 210 is too long, the second duration control unit 430 outputs an over-absorption protection signal to the switch control unit 224, and the switch control unit 224 controls the first switch unit 210 to keep turning off. In this embodiment, the airflow detection unit is electrically connected with the over-suction protection unit, the over-suction protection unit is reset by edge triggering, the over-suction protection unit is unlocked and returns to normal, and a turn-on signal is output to the switch control unit. Specifically, the airflow detecting unit is electrically connected to the second duration control unit, and when the airflow detecting unit 221 detects a change from airflow to no airflow or from no airflow to airflow, the second duration control unit is triggered to reset, for example, triggered by a rising edge or a falling edge, and then returns to a normal state. In the normal state, the over-suction protection unit outputs a turn-on signal to the switch control unit 224, and whether the first switching unit 210 operates is determined by the airflow detection unit 221. When the airflow detecting unit 221 outputs the turn-on signal to the switch control unit 224, the over-suction protection unit still outputs the turn-on signal at this time, so that the switch control unit 224 controls the first switch unit 210 to operate, and the second timing unit 420 starts timing. In addition, in other embodiments of the present application, unlocking may also be implemented in other manners to enable the over-suction protection unit to return to the normal state, for example, the over-suction protection unit is triggered to return to the normal state by an activation key or a combination of the activation key and a duration.

Referring to fig. 3b, in the present embodiment, the second timing unit 420 includes a first reference frequency generating unit 422 and a second timing subunit 421, the first reference frequency generating unit 422 is electrically connected to the second timing subunit 421, one end of the second timing subunit 421 is electrically connected to the output end of the over-suction comparing unit 410, the other end of the second timing subunit 421 is electrically connected to the second duration control unit 430, and the output end of the second duration control unit 430 is directly or indirectly electrically connected to the switch control unit 224. In an embodiment of the present application, the second timing subunit 421 counts the number of cycles of the first reference frequency generating unit 422, and the product of the count and the frequency cycle is the duration. In another embodiment of the present application, the second timing subunit 421 may also represent the time length by counting the obtained number of cycles, but may also represent the time length by other conventional data. In this embodiment, the second timing subunit 421 starts timing by the first type of edge triggering or the first type of level triggering, stops timing by the second type of edge triggering or the second type of level triggering, and sets the timing duration to zero. In this embodiment, the first reference frequency generating unit 422 may be shared with other units in the system control module 272, which may save cost. The first reference frequency generating unit 422 is, for example, an oscillator or the like.

In this embodiment, no matter the electronic cigarette is working or not, the first reference frequency generating unit 422 of the second timing unit 420 always needs to work, which results in higher energy consumption, in order to save energy consumption, in other embodiments of the present application, referring to fig. 3c, the second timing unit 420 includes a second reference frequency generating unit 442 and a second timing subunit 421, the second reference frequency generating unit 442 is located between the second timing subunit 421 and the over-suck comparing unit 410, specifically, an input end of the second reference frequency generating unit 442 is electrically connected to an output end of the over-suck comparing unit 410, an output end of the second reference frequency generating unit 442 is electrically connected to the second timing subunit 421, the second reference frequency generating unit 442 triggers to generate a frequency signal through a first edge or a first level, and triggers to stop generating the frequency signal through a second edge or a second level, and thus power consumption can be reduced. Specifically, the over-suction comparing unit 410 determines whether the voltage of the atomization end AT is greater than a first reference voltage Vref1, when the voltage of the atomization end AT is changed from being lower than the first reference voltage Vref1 to being higher than the first reference voltage Vref1, the output level signal of the over-suction comparing unit 410 is changed, the second reference frequency generating unit 442 triggers generation of a frequency signal when receiving the edge signal or the changed level signal, the second timing subunit 421 starts timing according to the received frequency signal, and outputs the timed real-time duration to the second duration control unit 430; when the voltage of the atomization end AT is changed from being higher than the first reference voltage Vref1 to being lower than the first reference voltage Vref1, the second reference frequency generation unit 442 stops generating the frequency signal, and the second timing subunit 421 stops timing and resets the timing duration to 0. The relationship between the second duration control unit 430 and the switch control unit 224 is described above, and will not be described herein. In this embodiment, the second timing subunit 421 and the second duration control unit 430 may be combined into one circuit module, or may be separately implemented.

In this embodiment, the second preset time duration is adjustable, and the following three ways of adjusting the second preset time duration are exemplified, but not limited to the following three ways, and those skilled in the art may design other conventional time duration adjustable circuits according to actual needs. However, the present application is not limited thereto, and in other embodiments of the present application, the first preset time period may not be adjustable.

1. Referring to fig. 3d, the first reference frequency generating unit 422 or the second reference frequency generating unit 442 includes a frequency comparator 331, a frequency switching unit PK1, a first current source 310, and a frequency capacitance terminal PC (pin). The first terminal of the first current source 310 is electrically connected to the battery terminal BAT1, the second terminal of the first current source 310 is electrically connected to the first terminal of the frequency switch unit PK1, an input terminal of the frequency comparator 331, and the frequency capacitor terminal PC, respectively, another input terminal of the frequency comparator 331 is connected to the preset first frequency reference voltage PVref1, the output terminal of the frequency comparator 331 is electrically connected to the control terminal of the frequency switch unit PK1, the second terminal of the frequency switch unit PK1 is electrically connected to the first ground terminal GND1, the frequency capacitor terminal PC is electrically connected to one terminal of the frequency capacitor C2, and the other terminal of the frequency capacitor C2 is grounded. The operation principle of generating the frequency or period in fig. 3d is conventional in the art and will not be described herein. The frequency period of the first reference frequency generating unit 422 or the second reference frequency generating unit 442 is in a linear relationship with the capacitance value of the capacitor, and the period is also in a linear relationship with the second preset time period, so that the second preset time period is in a proportional relationship with the capacitance value of the frequency capacitor C2, and the parameter value of the first reference frequency generating unit 422 or the second reference frequency generating unit 442 is determined after the chip is manufactured, so that the second preset time period can be changed by changing the capacitance value of the frequency capacitor C2. Here, the frequency capacitor C2 is external, that is, not located on the chip, and the frequency capacitor end PC can obtain a second preset duration through electrically connecting the frequency capacitors C2 with different capacitances, so that the second preset duration is adjustable. In addition, in other embodiments, the first reference frequency generating unit 422 or the second reference frequency generating unit 442 further includes a first frequency capacitor C2, the second frequency capacitor C2 may be externally connected to the frequency capacitor PC, at this time, the first frequency capacitor C2 and the second frequency capacitor C2 are arranged in parallel, when the frequency capacitor PC is suspended, the second preset time duration is determined by the built-in first frequency capacitor C2, when the frequency capacitor PC is externally connected to the second frequency capacitor C2 with different capacitance values, at this time, the second preset time duration is determined by the first frequency capacitor C2 and the second frequency capacitor C2 together, and the second preset time duration is adjustable.

2. Referring to fig. 3e, the first reference frequency generating unit 422 or the second reference frequency generating unit 442 includes a frequency comparator 331, a frequency operational amplifier 332, a frequency switching unit PK1, a first current source 310, a second current source 320, a frequency capacitor C2 and a frequency resistor PR (pin), the first current source 310 includes a first frequency MOS transistor PM1, and the second current source 320 includes a second frequency MOS transistor PM 2. Wherein, the source of the first frequency MOS transistor PM1 and the source of the second frequency MOS transistor PM2 are both electrically connected to the battery terminal BAT1, the gate of the first frequency MOS transistor PM1 and the gate of the second frequency MOS transistor PM2 are electrically connected to the output terminal of the frequency operational amplifier 332, one input terminal of the frequency operational amplifier 332 is connected to a preset second frequency reference voltage PVref2, the other input terminal of the frequency operational amplifier 332 is electrically connected to the drain of the second frequency MOS transistor PM2, the drain of the second frequency MOS transistor PM2 is also electrically connected to the frequency resistance terminal PR, the drain of the first frequency MOS transistor PM1 is electrically connected to the first terminal of the frequency switching unit PK1, one input terminal of the frequency comparator 331 and the first terminal of the frequency capacitor C2, the other input terminal of the frequency comparator 331 is connected to a preset first frequency reference voltage PVref1, the output terminal of the frequency comparator 331 is electrically connected to the control terminal of the frequency switching unit PK1, the second terminal of the frequency switch unit PK1 is connected to the first ground terminal GND1, the second terminal of the frequency capacitor C2 is connected to the first ground terminal GND1, the frequency resistor PR is electrically connected to the first terminal of the frequency resistor R2, and the second terminal of the frequency resistor R2 is grounded. The operation principle of fig. 3e for generating frequency is conventional in the art and will not be described herein. In this embodiment, the frequency generated by the first reference frequency generating unit 422 or the second reference frequency generating unit 442 is linearly related to the current flowing through the capacitor, the period is the reciprocal of the frequency, and the period is linearly related to the second preset time period, so that the second preset time period is proportional to the resistance value of the frequency resistor R2, and the parameter of the first reference frequency generating unit 422 or the second reference frequency generating unit 442 is determined after the chip is manufactured, so that the current flowing through the capacitor is determined by the frequency resistor R2, and thus the second preset time period can be changed by changing the resistance value of the frequency resistor R2. Here, the frequency resistor R2 is external, and the frequency resistor PR can obtain different second preset durations by connecting the frequency resistors R2 with different resistance values, so that the second preset duration is adjustable. Here, the first current source 310 and the second current source 320 constitute a mirror current source, a proportional current source, or the like. In addition, the first reference frequency generating unit 422 or the second reference frequency generating unit 442 further includes a first frequency resistor R2, which may be externally connected to a second frequency resistor R2 through a frequency resistor PR, where the first frequency resistor R2 and the second frequency resistor R2 are arranged in parallel, when the frequency resistor PR is suspended, a second preset duration is determined by the first frequency resistor R2, when the frequency resistor PR is externally connected to a second frequency resistor R2 having different resistance values, the second preset duration is determined by the first frequency resistor R2 and the second frequency resistor R2, and the second preset duration is adjustable.

3. The magnitude of the current output to the frequency capacitor C2 can also be adjusted by a microcontroller or by a built-in multi-path current source with different current values, so as to adjust the second preset time duration.

In this embodiment, different users, different brands, different manufacturers and the like have different requirements on the second preset time, and the second preset time is adjustable, so that the requirements of different users, different brands and different manufacturers can be met, and the market competitiveness of the system control circuit is improved.

In this embodiment, obtaining the voltage of the atomization end AT includes directly collecting or indirectly collecting, where the directly collected voltage is the voltage of the atomization end AT, and the indirectly collected voltage is generally not equal to the voltage of the atomization end AT, for example, the voltage obtained through a voltage dividing resistor (the branch detection unit includes a voltage dividing resistor, please refer to the fifth and sixth embodiments) is smaller than the voltage of the atomization end AT. These are all conventional techniques or modifications in the art, which are intended to be within the scope of this application.

Second embodiment

Referring to fig. 5, fig. 5 is a circuit block diagram of an electronic cigarette according to a second embodiment of the present application, which is similar to the first embodiment, so that the undescribed portion of the present embodiment can refer to the first embodiment, and the main difference between the present embodiment and the first embodiment is that the first switch unit 210 is disposed below.

Referring to fig. 5, in the present embodiment, the first switch unit 210 is disposed below and the first switch unit 210 is disposed inside, that is, a first end of the first switch unit 210 is electrically connected to a first ground GND1, the first ground GND1 is electrically connected to a negative electrode of the battery 110 or a negative electrode of the battery 110 via the second switch unit 140, a second end of the first switch unit 210 is electrically connected to an atomization end AT, the atomization end AT is electrically connected to one end of the heating element 250, the other end of the heating element 250 is electrically connected to a battery end BAT1, the battery end BAT1 is electrically connected to a positive electrode of the battery 110 or is electrically connected to a positive electrode of the battery 110 via the second switch unit 140, and the atomization end AT is a connection point (hereinafter referred to as an atomization connection point) between the first switch unit 210 and the heating element 250. In addition, in another embodiment of the present application, please refer to fig. 6, the first switch unit 210 is disposed downward and the first switch unit 210 is disposed outward, and AT this time, the atomization end AT is electrically connected to the atomization connection point.

In this embodiment, when the first switch unit 210 is turned on, the heat-generating branch has a larger current flowing, generally at an ampere level, such as 0.5A, 1A, 2A, etc., the voltage of the atomization connection point is the voltage of the first ground terminal GND1 plus the voltage drop of the first switch unit 210, the voltage drops of the first switch unit 210 and the second switch unit 140 are generally at a millivolt level, the voltage of the first ground terminal GND1 is close to 0 or the voltage of the system terminal VM, generally at 0 or millivolt level, the voltage of the atomization connection point is generally less than 0.5V, and the voltage of the atomization connection point is smaller and at a low level; when the first switch unit 210 is turned off, the heating branch is turned off AT this time, no current flows through the heating branch, the voltage of the atomization connection point is the voltage of the battery terminal BAT1, the voltage of the atomization terminal AT relative to the first ground terminal GND1 is the voltage of the battery terminal BAT1 AT this time, the voltage of the battery terminal BAT1 is a high level, the voltage of the battery terminal BAT1 is the voltage of the battery 110 or the voltage of the system terminal VM, the voltage drop of the second switch unit 140 is generally in a microvolt level, and the voltage of the atomization connection point is generally greater than 3.2V AT this time, so that whether the first switch unit 210 is turned on or off can be determined by determining the voltage AT the connection point between the first switch unit 210 and the heating element 250, and whether the heating element 250 is heating is further determined.

Referring to fig. 3a, in the present embodiment, the system control unit 220 includes an airflow detecting unit 221 and a switch control unit 224. The airflow detecting unit 221 is electrically connected to the airflow detecting element 240, the airflow detecting unit 221 is electrically connected to the switch control unit 224, and the switch control unit 224 is electrically connected to the control terminal of the first switch unit 210.

In this embodiment, the system control module 272 further includes a branch detection unit, where the branch detection unit is configured to obtain a second detection voltage, and the second detection voltage is used to represent whether the heating branch is turned on. In this embodiment, the branch detecting unit includes an atomization end AT, and a voltage of the atomization end AT is used to determine the second detection voltage. In this embodiment, the voltage of the atomization end AT is the second detection voltage, but in other embodiments, the voltage of the atomization end AT may be converted to obtain the second detection voltage. In this embodiment, the system control module 272 can determine whether the heating branch is turned on by the voltage of the atomization end AT, and further determine whether the heating element 250 is heating.

Referring to fig. 3b, in the embodiment, the over-suck protection unit 223 includes an over-suck comparison unit 410, the over-suck comparison unit 410 is, for example, a voltage comparator, one input terminal of the over-suck comparison unit 410 is electrically connected to the atomization terminal AT, the other input terminal of the over-suck comparison unit 410 is electrically connected to a third reference voltage generation unit, the third reference voltage generation unit generates a second reference voltage Vref2 and inputs the second reference voltage Vref2 to the over-suck comparison unit 410, in the embodiment, the second reference voltage Vref2 is generally between 0.5V and 3.2V, for example, 0.5V, 1V, 1.5V, 2V, 2.5V, 3V, 3.2V, and the like.

In this embodiment, when the first switch unit 210 is turned off, the heat-generating branch is turned off AT this time, no current flows, the voltage of the atomization terminal AT is equal to the voltage of the battery terminal BAT1, the voltage of the battery terminal BAT1 is generally greater than 3.2V and greater than the second reference voltage Vref2, the overdriving comparison unit 410 outputs the second level signal, when the first switch unit 210 is turned on, the heat-generating branch is turned on AT this time, a large current flows through the heat-generating branch, and is in an ampere level, the voltage of the atomization terminal AT is close to the voltage of the first ground terminal GND1 AT this time, the voltage of the first ground terminal GND1 is 0 or millivolt level (the voltage drop of the second switch unit 140 and the voltage drop of the first switch unit 210 are millivolt level), and is less than the second reference voltage Vref2, and the overdriving comparison unit 410 outputs the first level signal.

In this embodiment, when an air flow flows, the air flow detecting unit 221 is triggered, the first switching unit 210 is turned on and turned on, the over-suction comparing unit 410 determines that the voltage of the atomization end AT is less than the second reference voltage Vref2, AT this time, the over-suction comparing unit 410 outputs a first level signal, the second timing unit 420 starts timing (edge triggering or level triggering), when no air flow flows (or is AT a low level of the PWM signal or a low level of the PFM signal), the first switching unit 210 is turned off and turned off, the heating branch is not turned on, no current flows on the heating branch, AT this time, the over-suction comparing unit 410 determines that the voltage of the atomization end AT is greater than the second reference voltage Vref2, the over-suction comparing unit 410 outputs a second level signal, the second timing unit 420 stops timing (edge triggering or level triggering) and sets a timing duration of the second timing unit 420 to zero, so that the second timing unit 420 can obtain a heating duration of the heating element 250 in real time and output the heating duration to the second control unit Element 430. In this embodiment, the first level signal is, for example, a high level or a low level, and the second level signal corresponds to, for example, a low level or a high level. The edge trigger is, for example, a rising edge trigger or a falling edge trigger, and the level trigger is, for example, a high level trigger or a low level trigger.

When the first switch unit 210 is continuously turned on due to a non-airflow or the first switch unit 210 is continuously turned on due to an airflow (for example, the third driving method) or the first switch unit 210 is continuously turned on due to other reasons, the second timing unit 420 keeps timing, and does not stop timing and does not set to zero, the second timing unit 420 outputs the timing duration to the second duration control unit 430 in real time, when the second duration control unit 430 knows that the duration of the first switch unit 210 being turned on is greater than or equal to the second preset duration, the second duration control unit 430 outputs an over-suction protection signal to the switch control unit 224, the switch control unit 224 controls the first switch unit 210 to keep turning off, the first switch unit 210 keeps stopping working, when the first switch unit 210 being turned off, the heating branch is turned off, at this time, the first switch unit 210 stops working, and the heating element 250 does not reheat, the temperature of the first switch unit 210 and the surrounding temperature thereof will not rise any more, which can prevent the first switch unit 210 or the system control module 272 from causing damage to the electronic cigarette due to high temperature damage, especially from causing fire; moreover, this embodiment is through whether the direct detection branch road that generates heat switches on, and the indirect detection mode in the background art relatively detects more accurately. Moreover, this embodiment is whether the branch that generates heat is directly listened and is switched on, no matter the air current reason causes the branch that generates heat to switch on, or causes the branch that generates heat to switch on by non-air current reason, and this application homoenergetic is suitable for.

Referring to fig. 5 and fig. 3a, in the embodiment, when the second duration control unit 430 knows that the duration of the conduction of the first switching unit 210 is greater than or equal to the second preset duration, the second duration control unit 430 outputs the over-absorption protection signal to the switching control unit 224, and meanwhile, the second duration control unit 430 locks and outputs the over-absorption protection signal to the switching control unit 224, and controls the timing duration of the second timing unit 420 to be set to zero, which is favorable for reducing energy consumption. In this embodiment, the over-suction protection signal is, for example, an off-cut signal, or a signal obtained by processing the off-cut signal, as long as the first switching unit 210 can be controlled to be turned off by the switching control unit 224. In the present embodiment, the second preset time period ranges from 4s to 15s, for example, 4s, 5s, 6s, 7s, 8s, 9s, 10s, 11s, 12s, 13s, 14s, 15s, and so on.

In the present embodiment, the switch control unit 224 includes a logic gate circuit, which is, for example, an and gate, two input terminals of the and gate are electrically connected to the over-suction protection unit 223 and the airflow detection unit 221, respectively, and an output terminal of the and gate is electrically connected to other circuit units in the switch control unit 224. In the present embodiment, only when the over-suction protection unit 223 and the airflow detection unit 221 both output the turn-on signal to the switch control unit 224, the switch control unit 224 controls the first switch unit 210 to turn on, and in a normal case, the over-suction protection unit 223 both outputs the turn-on signal. In addition, in other embodiments of the present application, the logic gate circuit may also be a combination of an and gate and a not gate, a combination of an or gate and a nand gate, an and gate, an or gate, and a not gate to implement the desired signal, the not gate may be located in front of or behind the and gate or the or gate, the number of the not gate, the and gate, or gate may be one or more, and those skilled in the art may set the desired functions according to actual needs.

In this embodiment, when the second duration control unit 430 determines that the timing duration of the second timing unit 420 is greater than or equal to the second preset duration, which indicates that the working time of the first switching unit 210 is too long, the second duration control unit 430 outputs the over-suction protection signal to the switching control unit 224, and the switching control unit 224 controls the first switching unit 210 to keep turning off. In this embodiment, the airflow detecting unit 221 is electrically connected to the over-suction protection unit, the over-suction protection unit is reset by edge triggering, the over-suction protection unit is unlocked and returns to normal, and a turn-on signal is output to the switch control unit 224. Specifically, the airflow detecting unit is electrically connected to the second duration control unit, and when the airflow detecting unit 221 detects a change from airflow to no airflow or from no airflow to airflow, the second duration control unit is triggered to reset, for example, triggered by a rising edge or a falling edge, and then returns to a normal state. In the normal state, the over-suction protection unit outputs a turn-on signal to the switch control unit 224, and whether the first switching unit 210 operates is determined by the airflow detection unit 221. When the airflow detecting unit 221 outputs the turn-on signal to the switch control unit 224, the over-suction protection unit still outputs the turn-on signal at this time, so that the switch control unit 224 controls the first switch unit 210 to operate, and the second timing unit 420 starts timing. In addition, in other embodiments of the present application, unlocking may also be implemented in other manners to enable the over-suction protection unit to return to the normal state, for example, the over-suction protection unit is triggered to return to the normal state by an activation key or a combination of the activation key and a duration.

Referring to fig. 3b or fig. 3c, in the present embodiment, the second timing unit 420 includes a first reference frequency generating unit 422 and a second timing subunit 421, or the second timing unit 420 includes a second-level reference frequency generating unit and a second timing subunit 421, for details, see the first embodiment, which is not described herein again.

In this embodiment, the second preset duration is adjustable, and the manner in which the second preset duration is adjustable has been described in the first embodiment, and is not described herein again. However, the present application is not limited thereto, and in other embodiments of the present application, the second preset time period may not be adjustable.

Third embodiment

Referring to fig. 7a, fig. 7a is a circuit block diagram of an electronic cigarette according to a third embodiment of the present application, which is similar to the first and second embodiments, so that the undescribed portion of the present embodiment can refer to the first and second embodiments, and the present embodiment is mainly different from the first and second embodiments in that whether the heating branch is turned on is not detected through the atomizing terminal AT.

Referring to fig. 7a and 7b, in the present embodiment, the atomizing assembly 200 further includes a second detecting resistor 271, the second detecting resistor 271 is connected in series with the first switch unit 210 and the heating element 250 to form a heating branch, and the resistance of the second detecting resistor 271 is generally in the milliohm range, for example, 1 milliohm to 100 milliohm.

In the present embodiment, the first switch unit 210 is disposed on the top and the first switch unit 210 is disposed inside. In the present embodiment, the first terminal of the first switch unit 210 is electrically connected to the battery terminal BAT1, the battery terminal BAT1 is electrically connected to the positive electrode of the battery 110, or is electrically connected to the positive electrode of the battery 110 via the second switch unit 140, the second terminal of the first switch unit 210 is electrically connected to the atomization terminal AT, the atomization terminal AT is electrically connected to one terminal of the heating element 250, the other terminal of the heating element 250 is connected to one terminal of the second detection resistor 271, the other terminal of the second detection resistor 271 is connected to the first ground terminal GND1, and the first ground terminal GND1 is electrically connected to the negative electrode of the battery 110 via the second switch unit 140, or is electrically connected to the negative electrode of the battery 110. In addition, in other embodiments of the present application, the positions of the second detection resistor 271 and the heating element 250 may be exchanged.

Referring to fig. 7a, in the present embodiment, the system control module 272 includes a branch detection unit, the branch detection unit is electrically connected to the heating branch, the branch detection unit is configured to obtain a second detection voltage, and the second detection voltage is used to represent whether the heating branch is turned on. In this embodiment, the second detection voltage is one value when the heating branch is turned on, and the second detection voltage is another different value when the heating branch is turned off. In the present embodiment, the system control unit 220 includes an over-suction protection unit 223, and the over-suction protection unit 223 is electrically connected to the branch detection unit and the switch control unit 224, respectively.

In this embodiment, the branch detecting unit includes a heat generation detecting terminal GX electrically connected to a connection of the second detecting resistor 271 and the heat generating element 250, and a voltage of the heat generation detecting terminal GX is used to determine the second detecting voltage. In this embodiment, the voltage of the heat generation detecting terminal GX is the second detecting voltage, but in other embodiments, the voltage of the heat generation detecting terminal GX may be converted to obtain the second detecting voltage, for example, the voltage drop of the second detecting resistor 271. In the present embodiment, the heat generation detecting terminal GX is electrically connected to one input terminal of the over-pull comparing unit 410 of the over-pull protection unit, the other input terminal of the over-pull comparing unit 410 is electrically connected to the third reference voltage generating unit 138, and the third reference voltage generating unit 138 is configured to generate the first reference voltage Vref 1.

In this embodiment, when an airflow flows, the airflow detecting unit 221 is triggered, the first switching unit 210 is turned on, and at this time, the current on the heat generating branch is large and is in an ampere level, for example, 0.5A, 1A, 2A, and the like, the voltage of the heat generating detecting terminal GX is the sum of the voltage of the first ground terminal GND1 and the voltage drop of the second detecting resistor 271, and the voltage drop of the second switching unit 140 and the voltage drop of the second detecting resistor 271 are generally in a millivolt level; when no airflow flows, the first switching unit 210 is turned off, no current flows through the heat branch, the voltage of the heat detection terminal GX is equal to the voltage of the first ground terminal GND1, and the voltage drop of the second switching unit 140 is generally in the microvolt level, so that the voltage of the heat detection terminal GX is in the microvolt level or 0. In the embodiment, the first reference voltage Vref1 is greater than the voltage of the first ground GND1 when the first switch unit 210 is turned off, and is less than the voltage of the first ground GND1 plus the voltage drop of the second detection resistor 271 when the first switch unit 210 is turned on. Therefore, whether the first switch unit 210 is turned on or not can be known by determining the voltage of the heat generation detecting terminal GX and the first reference voltage Vref1, in this embodiment, the range of the first reference voltage Vref1 is between several tens microvolts and several tens millivolts, for example, 100uV, 200uV, 300uV, 400uV, 500uV, 600uV, 700uV, 800uV, 900uV, 1mV, 5mV, 10mV, 20mV, 30mV, 40mV, 50mV, etc., and those skilled in the art can set the voltage according to actual needs.

In this embodiment, how to trigger the over-suction protection after the over-suction comparing unit 410 obtains the voltage of the detection end and the third reference voltage may refer to the first embodiment and the second embodiment, which is not described herein again.

In addition, the position of the second detecting resistor 271 is not limited to that shown in fig. 7a, and in another embodiment of the present application, please refer to fig. 7c, the first switch unit 210 is disposed on top, and the first switch unit 210 is disposed outside. In this embodiment, one end of the second detection resistor 271 is electrically connected to the battery terminal BAT1, the battery terminal BAT1 is electrically connected to the positive electrode of the battery 110, or is electrically connected to the positive electrode of the battery 110 via the second switch unit 140, the other end of the second detection resistor 271 is electrically connected to the first end of the first switch unit 210, the second end of the first switch unit 210 is electrically connected to the atomization terminal AT, the atomization terminal AT is electrically connected to one end of the heating element 250, the other end of the heating element 250 is electrically connected to the first ground GND1, and the first ground GND1 is electrically connected to the negative electrode of the battery 110 via the second switch unit 140, or is electrically connected to the negative electrode of the battery 110. In the present embodiment, the heating detection terminal GX is electrically connected to a connection between the first switch unit 210 and the second detection resistor 271, and the voltage of the heating detection terminal GX is used to determine the second detection voltage, for example, the voltage of the heating detection terminal GX is the second detection voltage. When the first switch unit 210 is turned on, the current on the heat-generating branch is greater at the ampere level, for example, 0.5A, 1A, 2A, etc., the voltage of the heat-generating detection terminal GX is the voltage of the battery terminal BAT1 minus the voltage drop of the second detection resistor 271, and the voltage drop of the second switch unit 140 and the voltage drop of the second detection resistor 271 are generally at the millivolt level; when the first switch unit 210 is turned off, no current flows through the heat-generating branch, the voltage of the heat-generating detection terminal GX is equal to the voltage of the battery terminal BAT1, and the voltage drop of the second switch unit 140 is generally in the microvolt level. In this embodiment, one input terminal of the overdraw comparison unit 410 is electrically connected to the heat generation detection terminal GX, and the other input terminal is connected to the second reference voltage Vref 2. In this embodiment, the second reference voltage Vref2 is smaller than the voltage of the battery terminal BAT1 when the first switch unit 210 is turned off, and is larger than the voltage of the battery terminal BAT1 minus the voltage drop of the second detection resistor 271 when the first switch unit 210 is turned on. Therefore, whether the first switch unit 210 is turned on or not can be known by determining whether the voltage of the heating detection terminal GX is greater than the second reference voltage Vref2, and further whether the heating branch is turned on or not can be known. In addition, in other embodiments of the present application, the positions of the second detection resistor 271 and the first switch unit 210 may be exchanged. The on-resistance of the first switching unit 210 is generally in the milliohm range.

In addition, the position of the second detecting resistor 271 is not limited to that shown in fig. 7a, and in another embodiment of the present application, please refer to fig. 7d, the first switch unit 210 is disposed downward and the first switch unit 210 is disposed inward. In this embodiment, one end of the second detection resistor 271 is electrically connected to the battery terminal BAT1, the battery terminal BAT1 is electrically connected to the positive electrode of the battery 110, or is electrically connected to the positive electrode of the battery 110 via the second switch unit 140, the other end of the second detection resistor 271 is electrically connected to one end of the heating element 250, the other end of the heating element 250 is connected to the atomization terminal AT, the atomization terminal AT is electrically connected to one end of the first switch unit 210, the other end of the first switch unit 210 is electrically connected to the first ground GND1, and the first ground GND1 is electrically connected to the negative electrode of the battery 110 via the second switch unit 140, or is electrically connected to the negative electrode of the battery 110. In the present embodiment, the heat generation detecting terminal GX is electrically connected to the connection between the heat generating element 250 and the second detecting resistor 271, and the voltage of the heat generation detecting terminal GX is used to determine the second detecting voltage, for example, the voltage of the heat generation detecting terminal GX is the second detecting voltage. In this embodiment, when the first switch unit 210 is turned on, the current on the heating branch is large and is in an ampere level, the voltage of the heating detection terminal GX is obtained by subtracting the voltage drop of the second detection resistor 271 from the voltage of the battery terminal BAT1, and the voltage drop of the second switch unit 140 and the voltage drop of the second detection resistor 271 are generally in a millivolt level; when the first switch unit 210 is turned off, no current flows through the heat-generating branch, the voltage of the heat-generating detection terminal GX is equal to the voltage of the battery terminal BAT1, and the voltage drop of the second switch unit 140 is generally in the microvolt level. In this embodiment, one input terminal of the overdriving comparison unit 410 is electrically connected to the heat generation detection terminal GX, and the other input terminal is connected to the second reference voltage Vref 2. In this embodiment, the second reference voltage Vref2 is smaller than the voltage of the battery terminal BAT1 when the first switch unit 210 is turned off, and is larger than the voltage of the battery terminal BAT1 minus the voltage drop of the second detection resistor 271 when the first switch unit 210 is turned on. Accordingly, whether the first switching unit 210 is turned on can be known by determining whether the voltage of the heat generation detecting terminal GX is greater than the second reference voltage Vref 2. In addition, in other embodiments of the present application, the positions of the second detection resistor 271 and the heating element 250 may be exchanged.

In addition, the position of the second detecting resistor 271 is not limited to that shown in fig. 7a, and in another embodiment of the present application, please refer to fig. 7e, the first switch unit 210 is disposed downward and the first switch unit 210 is disposed outward. In the present embodiment, one end of the heating element 250 is electrically connected to the battery terminal BAT1, the battery terminal BAT1 is electrically connected to the positive electrode of the battery 110, or is electrically connected to the positive electrode of the battery 110 via the second switch unit 140, the other end of the heating element 250 is connected to the atomization terminal AT, the atomization terminal AT is electrically connected to one end of the first switch unit 210, the other end of the first switch unit 210 is electrically connected to one end of the second detection resistor 271, the other end of the second detection resistor 271 is electrically connected to the first ground GND1, and the first ground GND1 is electrically connected to the negative electrode of the battery 110 via the second switch unit 140, or is electrically connected to the negative electrode of the battery 110. In the present embodiment, the heat generation detection terminal GX is electrically connected to a connection point of the first switch unit 210 and the second detection resistor 271, and a voltage of the heat generation detection terminal GX is used to determine the second detection voltage, for example, the voltage of the heat generation detection terminal GX is the second detection voltage. In this embodiment, when the first switch unit 210 is turned on, the current on the heat-generating branch is at an ampere level, the voltage of the heat-generating detection terminal GX is the sum of the voltage of the first ground terminal GND1 and the voltage drop of the second detection resistor 271, and the voltage drop of the second switch unit 140 and the voltage drop of the second detection resistor 271 are generally at a millivolt level; when the first switch unit 210 is turned off, no current flows through the heat branch, the voltage of the heat detection terminal GX is equal to the voltage of the first ground terminal GND1, and the voltage drop of the second switch unit 140 is typically in the microvolt level. In the present embodiment, one input terminal of the overdriving comparison unit 410 is electrically connected to the heat generation detection terminal GX, and the other input terminal is connected to the first reference voltage Vref 1. Thus, the first reference voltage Vref1 is less than the voltage of the first ground GND1 plus the voltage drop of the second sensing resistor 271 when the first switch unit 210 is turned on, and greater than the voltage of the first ground GND1 when the first switch unit 210 is turned off. Accordingly, whether the first switching unit 210 is turned on can be known by determining whether the voltage of the heat generation detecting terminal GX is greater than the first reference voltage Vref 1. In addition, in other embodiments of the present application, the positions of the second detection resistor 271 and the first switch unit 210 may be exchanged.

In addition, in other embodiments of the present application, the second detection resistor 271 may also be connected in series to other suitable positions of the heat generating branch, and those skilled in the art may set the second detection resistor according to actual needs.

Fourth embodiment

In the first to third embodiments, when the switch control unit 224 drives the first switch unit 210 to operate in the PWM mode or the PFM mode, the PWM mode and the PFM mode include the on-time and the off-time in one cycle, the first switch unit 210 is turned on at the on-time, and turned off at the off-time, and because only one second timing unit 420 is provided, a problem may occur in the timing of the second timing unit 420 (reset and clear at the off-time), at this time, the over-smoking protection mechanisms of the above three embodiments are no longer applicable, and effective over-smoking protection cannot be provided for the electronic cigarette. To completely solve this problem, the present application innovatively provides a fourth embodiment, and parts not described in the present application may be referred to the first to third embodiments.

In the present embodiment, the first switching unit 210 may be driven by a PWM method or a PFM method. Referring to fig. 2 and 8, in the present embodiment, the overdriving logic unit includes a second timing unit 420, a second duration control unit 430, a third timing unit 440, and a third duration control unit 450. An input end of the second timing unit 420 and an input end of the third timing unit 440 are electrically connected to an output end of the over-suction comparing unit 410, an output end of the second timing unit 420 is electrically connected to the second duration control unit 430, an output end of the second duration control unit 430 is electrically connected to a control end of the first switch unit 210 via the switch control unit 224, an output end of the third timing unit 440 is electrically connected to the third duration control unit 450, and an output end of the third duration control unit 450 is electrically connected to the second timing unit 420. In this embodiment, the second timing unit 420 triggers or clocks by a first type of edge, the third timing unit 440 triggers or clocks by a second type of edge, and the third timing unit 440 stops clocking by a first type of edge, and the third duration control unit 450 controls whether the second timing unit 420 stops clocking.

Specifically, in the present embodiment, when an air flow flows, the air flow detection unit 221 is triggered, and the system control unit 220 drives the first switching unit 210 to operate through a PWM signal or a PFM signal, where the PWM signal and the PFM signal include an on time and an off time in one cycle. When the voltage is on, the first switch unit 210 is turned on, the overdriving protection unit 223 determines that the first detection voltage is greater than the first reference voltage Vref1 (taking the first switch unit 210 as an example for explanation), at this time, the overdriving comparison unit 410 outputs a first level signal, the second timing unit 420 starts timing, and the second timing unit 420 outputs the timing duration to the second duration control unit 430; when the time is in the off time, at this time, the overdriving protection unit 223 determines that the first detection voltage is lower than the first reference voltage Vref1, at this time, the overdriving comparison unit 410 outputs the second level signal, the third timing unit 440 starts timing, the third timing unit 440 outputs the timing duration to the third duration control unit 450, and when the on time of the next cycle is reached, the third timing unit 440 receives the first level signal output by the overdriving protection unit 223 and triggers to stop timing, that is, the third timing unit 440 is used for timing the duration of the off time or the duration of the non-operation of the first switching unit 210. When the third duration control unit 450 receives that the duration counted by the third timing unit 440 is greater than or equal to the third preset duration, this time, it indicates that the first switching unit 210 is already in the non-operating state, i.e. it indicates that the received signal is not the PWM signal or the PFM signal, but completely turns off the signal of the first switching unit 210, at which time no airflow has flowed, the third period control unit 450 outputs a reset signal to the second timing unit 420, the second timing unit 420 stops timing and resets the timing period to zero, when the third duration control unit 450 receives that the duration counted by the third timing unit 440 is less than the third preset duration, at this time, it indicates that the first switching unit 210 is still driven by the PWM signal or the PFM signal, but the third duration control unit 450 does not output the reset signal to the second timing unit 420 during the off time, and the second timing unit 420 counts up. When the second duration control unit 430 knows that the duration timed by the second timing unit 420 is greater than or equal to the second preset duration, the second duration control unit 430 outputs an over-suction protection signal to control the first switch unit 210 to keep off, the first switch unit 210 keeps stopping working, after the first switch unit 210 is switched off, the heating branch is switched off, the first switch unit 210 keeps stopping working, at this time, the heating element 250 is not reheated, the first switch unit 210 does not generate heat any more, the temperature of the first switch unit 210 and the surrounding temperature thereof does not rise any more, and therefore, the electronic cigarette can be prevented from being damaged due to high-temperature damage of the first switch unit 210 or the system control module 272, and particularly, a fire can not occur.

In this embodiment, when the second duration control unit 430 determines that the timing duration of the second timing unit 420 is greater than or equal to the second preset duration, which indicates that the cumulative on-time of the first switch unit is longer, the second duration control unit 430 outputs the over-suck protection signal to the switch control unit 224, the switch control unit 224 controls the first switch unit 210 to keep turning off and turning off, and the first switch unit 210 is locked and turned off to enter the over-suck protection.

In this embodiment, the airflow detection unit is electrically connected with the over-suction protection unit, the over-suction protection unit is reset by edge triggering, the over-suction protection unit is unlocked and returns to normal, and a turn-on signal is output to the switch control unit. Specifically, the air flow detection unit is electrically connected to the second duration control unit, and when the air flow detection unit 221 detects a change from air flow to no air flow or from no air flow to air flow, the second duration control unit is triggered to reset, for example, by a rising edge or a falling edge, and returns to a normal state. In the normal state, the over-suction protection unit outputs a turn-on signal to the switch control unit 224, and whether the first switching unit 210 operates is determined by the airflow detection unit 221. When the airflow detecting unit 221 outputs the turn-on signal to the switch control unit 224, the over-suction protection unit still outputs the turn-on signal at this time, so that the switch control unit 224 controls the first switch unit 210 to operate, and the second timing unit 420 starts timing. In addition, in other embodiments of the present application, unlocking may also be implemented in other manners to enable the over-suction protection unit to return to the normal state, for example, the over-suction protection unit is triggered to return to the normal state by an activation key or a combination of the activation key and a duration.

In this embodiment, the third preset time period is greater than the maximum period of the PWM signal and the PFM signal, and the third preset time period is, for example, greater than or equal to 60ms, such as 60ms, 70ms, 80ms, 90ms, 100ms, 110ms, 120ms, 130ms, 140ms, 150ms, and the like. In the present embodiment, a ratio of the third preset time period to the second preset time period is, for example, less than 1: 10. The embodiment can solve the problem that various first switch units work for a long time, and is particularly suitable for the situation that the electronic cigarette works for multiple times and the distance between two adjacent working times is short, for example, the distance is less than a third preset time.

The manner in which the present embodiment solves the above problem can be applied to various manners in which the system control module drives the first switch unit. For example, when the system control unit 220 drives the heating element 250 to heat in the third manner (see the previous description of the present embodiment for the first driving manner and the second driving manner), at this time, the third timing unit 440 does not trigger to start timing, the timing duration is always 0, the third duration control unit 450 does not output the reset signal to the second timing unit 420 (the third duration control unit 450 outputs the reset signal only when the first switch unit 210 does not operate), the second timing unit 420 counts up, and when the second duration control unit 430 knows that the duration timed by the second timing unit 420 is greater than or equal to the second preset duration, the second duration control unit 430 outputs the over-suction protection signal to turn off the first switch unit 210.

In this embodiment, when the airflow detection is repeatedly and falsely triggered, as long as the interval time is less than the third preset time period, the second timing unit 420 will always time, and when the timing time period of the second timing unit 420 is greater than or equal to the second preset time period, the over-suction protection will be triggered, so as to prevent the problem that the temperature of the first switch unit 210 is continuously increased due to another smoking without timely heat dissipation.

Referring to fig. 8, in the present embodiment, the second timing unit 420 includes a first reference frequency generating unit 422 and a second timing subunit 421, the third timing unit 440 includes a third timing subunit 441, and the second timing unit 420 and the third timing unit 440 share one first reference frequency generating unit 422, so as to reduce the cost. The second timing subunit 421 and the third timing subunit 441 are electrically connected to the output end of the overdriving comparison unit 410, the second timing subunit 421 is electrically connected to the second duration control unit 430 and the first reference frequency generation unit 422, the third timing subunit 441 is electrically connected to the third duration control unit 450 and the first reference frequency generation unit 422, and the third duration control unit 450 is electrically connected to the second timing subunit 421. In this embodiment, the first reference frequency generating unit 422 is always operated, when the first switch unit 210 is turned on, the second timing subunit 421 is triggered to receive the frequency signal output by the first reference frequency generating unit 422, the frequency signal is, for example, a pulse signal, a sawtooth wave signal, a triangular wave signal, etc., the second timing subunit 421 starts timing, when the first switch unit 210 is turned off, the third timing subunit 441 is triggered to receive the frequency signal output by the first reference frequency generating unit 422, the third timing subunit 441 starts timing, when the first switch unit 210 is turned on again, the third timing subunit 441 stops receiving the frequency signal output by the first reference frequency generating unit 422, the third timing subunit 441 stops timing and resets and clears, when the third duration control unit 450 receives the duration that the third timing subunit 441 times is greater than or equal to a third preset duration, the third duration control unit 450 outputs a reset signal to the second timing subunit 421, and the second timing subunit 421 resets and sets to zero; when the third duration control unit 450 receives that the duration counted by the third timing subunit 441 is less than the third preset duration, the third timing subunit 441 does not output the reset signal. In other embodiments of the present application, second timing unit 420 and third timing unit 440 may not share first reference frequency generating unit 422, and may each have one first reference frequency generating unit 422. In this embodiment, the second timing subunit 421 and the second duration control unit 430 may be combined into a circuit module, or may be separately implemented, and the third timing subunit 441 and the third duration control unit 450 may be combined into a circuit module, or may be separately implemented; the second timing subunit 421, the second duration control unit 430, the third timing subunit 441, and the third duration control unit 450 can also be combined into one circuit module.

In this embodiment, no matter the electronic cigarette is operated or not, the first reference frequency generating unit 422 is operated all the time, so that the energy consumption is high, and in order to save the energy consumption, in other embodiments of the present application, please refer to fig. 9, the second timing unit 420 includes a second reference frequency generating unit 442 and a second timing subunit 421, the third timing unit 440 includes a third timing subunit 441, and the second timing unit 420 and the third timing unit 440 share one second reference frequency generating unit 442, so that the cost can be reduced. The second reference frequency generating unit 442 and the third timing subunit 441 are electrically connected to an output end of the over-suction comparing unit 410, the second timing subunit 421 and the third timing subunit 441 are electrically connected to the second reference frequency generating unit 442, the second timing subunit 421 is electrically connected to the second time duration controlling unit 430, the third timing subunit 441 is electrically connected to the third time duration controlling unit 450, and the third time duration controlling unit 450 is electrically connected to the second reference frequency generating unit 442 and the second timing subunit 421. In this embodiment, the second reference frequency generating unit 442 operates when the first switching unit 210 operates, and does not operate after a delay for a period of time when the first switching unit 210 does not operate, and thus, no frequency signal is generated and no frequency signal is generated, which can save energy consumption.

Specifically, in this embodiment, when the first switch unit 210 is turned on, the overdriving comparison unit 410 outputs a first level signal, the second reference frequency generation unit 442 is triggered to output a frequency signal, the second timing subunit 421 receives the frequency signal and starts timing, when the first switch unit 210 is turned off, the overdriving comparison unit 410 outputs a second level signal, the third timing subunit 441 is triggered to receive the frequency signal output by the second reference frequency generation unit 442, the third timing subunit 441 starts timing, when the first switch unit 210 is turned on again, the overdriving comparison unit 410 converts outputting the second level signal into outputting the first level signal, the third timing subunit 441 stops receiving the frequency signal output by the second reference frequency generation unit 442, the third timing subunit 441 stops timing and resets and clears, when the third duration control unit 450 receives the third timing subunit 441, the duration is greater than or equal to a third preset duration, at this time, indicating that the electronic cigarette is not working, the third duration control unit 450 outputs a reset signal to the second timing subunit 421 and the second reference frequency generating unit 442, the second reference frequency generating unit 442 does not work any more, the second reference frequency generating unit 442 stops generating the frequency signal, and meanwhile, the second timing subunit 421 resets to zero; when the third duration control unit 450 receives that the duration counted by the third timing subunit 441 is less than the third preset duration, the third timing subunit 441 does not output the reset signal. In addition, in other embodiments of the present application, the third time duration control unit 450 may also be electrically connected to the second reference frequency generation unit 442 and not electrically connected to the second timing subunit 421, at this time, when the third time duration control unit 450 receives that the time duration counted by the third timing subunit 441 is greater than or equal to a third preset time duration, which indicates that the electronic cigarette is not in operation, the third time duration control unit 450 outputs a reset signal to the second reference frequency generation unit 442, the second reference frequency generation unit 442 is not in operation, the second reference frequency generation unit 442 stops generating the frequency signal, the second timing subunit 421 does not receive the frequency signal, and the second timing subunit 421 automatically resets and sets to zero. In other embodiments of the present application, second timing unit 420 and third timing unit 440 may not share second reference frequency generation unit 442, and may each have one second reference frequency generation unit 442. In this embodiment, the second timing subunit 421 and the second duration control unit 430 may be combined into a circuit module, or may be separately implemented, and the third timing subunit 441 and the third duration control unit 450 may be combined into a circuit module, or may be separately implemented; the second timing subunit 421, the second duration control unit 430, the third timing subunit 441, and the third duration control unit 450 can also be combined into one circuit module.

In this embodiment, the second preset duration is adjustable, and the manner in which the second preset duration is adjustable is described in the first embodiment, and is not described herein again. In this embodiment, the third preset time period is adjustable, and please refer to the second preset time period adjustable manner for the third preset time period, which is not described herein again. In an embodiment of the present application, a ratio of the second preset time period to the third preset time period may be fixed. In addition, in other embodiments of the present application, the third preset time period may also be unadjustable.

A specific example is described below to illustrate the embodiment, for example, the second timing unit 420 triggers timing by a rising edge (or a high level), the third timing unit 440 triggers timing by a low level (or a falling edge), stops timing by a high level (or a rising edge) and sets zero, and the airflow detection unit 221 triggers the second duration control unit 430 to reset by a falling edge; when no airflow is converted into airflow, the airflow detecting unit 221 converts the output of the off/off signal (assuming that the off/off signal is at a low level) into the output of the on/off signal (assuming that the on/off signal is at a high level), the first switching unit 210 operates, when the first switching unit 210 is in an on time, the overdriving comparing unit 410 converts the output of the low level into the output of the high level, the second timing unit 420 is triggered to start timing at a rising edge, when the first switching unit 210 is in an off time, the overdriving comparing unit 410 converts the output of the high level into the output of the low level, the third timing unit 440 starts timing at the low level, and when the first switching unit 210 is continuously driven by the PWM signal or the PFM signal for a plurality of cycles (airflow always flows), the timing of the third timing unit 440 is always less than a third preset time period, the third time period control unit 450 does not output the reset signal, the second timing unit 420 counts time accumulatively all the time, the airflow detecting unit 221 outputs a turn-on signal all the time, when the timing duration of the second timing unit 420 is greater than or equal to a second preset duration, the second duration control unit 430 locks to output an over-suction protection signal to the switch control unit 224, and controls the second timing unit 420 to be set to zero at the same time, the switch control unit 224 controls the first switch unit 210 to keep out of work, at this time, the first switch unit 210 keeps off, when a user continuously inhales air, the airflow detecting unit 221 still outputs a turn-on signal at this time, and because the second duration control unit 430 locks to output the over-suction protection signal, the first switch unit 210 keeps off. When the user stops inhaling, at this time, the airflow detection unit 221 switches from outputting the on-signal to outputting the off-signal, and the airflow detection unit 221 controls the second duration control unit 430 to reset at the falling edge, so that the second duration control unit 430 is unlocked and returns to normal, the second duration control unit 430 outputs the on-signal to the switch control unit 224, at this time, because the airflow detection unit 221 outputs the off-signal to the switch control unit 224, the first switch unit 210 remains off, and when the user next inhales, the first switch unit 210 can normally operate. The arrangement can not only enable the electronic cigarette to work normally, but also prevent the problem that the temperature rise of the first switch unit 210 is high due to long working time. In addition, in other embodiments of the present application, the second timing unit 420 triggers timing by a falling edge, the third timing unit 440 triggers timing by a high level (or a rising edge), stops timing by a low level (or a falling edge), and the airflow detecting unit 221 triggers the second duration control unit 430 to reset by a rising edge, which can be implemented by adding a not gate or other logic gate circuit.

Fifth embodiment

In the first to fourth embodiments, whether the first switch unit 210 is turned on or off is determined by detecting the voltages of the atomization terminal AT and the second detection resistor 271, and whether the first switch unit 210 is turned on or off is determined by detecting whether the heating branch formed by the series connection of the heating element 250 and the first switch unit 210 has a conduction current. Parts not described in the present embodiment may be referred to in the first to fourth embodiments.

Referring to fig. 2, in the present embodiment, the first switch unit 210 is disposed on the first switch unit, and the system control module 272 includes a branch detection unit, where the branch detection unit is configured to obtain a second detection voltage, and the second detection voltage is used to represent whether the heating branch is turned on. In this embodiment, the branch detecting unit includes a current detecting unit and an atomization end AT, and the current detecting unit is configured to obtain a third detection voltage proportional to a current flowing through the heating branch, where the third detection voltage is used to determine a second detection voltage, and in this embodiment, the third detection voltage is the second detection voltage and is used to indicate whether a current flows in the heating branch.

Specifically, referring to fig. 2 and 10 in combination, in the present embodiment, the current detection unit includes a first detection MOS transistor JM1, a first detection operational amplifier JOPA1, a second detection MOS transistor JM2 and a third detection resistor JR3, wherein a gate of the first detection MOS transistor JM1 is electrically connected to the gate of the first switch unit 210, a source is electrically connected to the battery terminal BAT1, a drain is electrically connected to a common terminal of the first detection operational amplifier JOPA1, an opposite terminal of the first detection operational amplifier JOPA1 is electrically connected to the fogging terminal AT, the common terminal of the first detection operational amplifier JOPA1 is further electrically connected to a source of the second detection MOS transistor JM2, an output terminal of the first detection operational amplifier JOPA1 is electrically connected to a gate of the second detection MOS transistor JM2, a drain of the second detection MOS transistor JM2 is electrically connected to one terminal of the third detection resistor JR3, and the other terminal of the third detection resistor JR3 is electrically connected to the first GND terminal JR 1. When the first switch unit 210 is turned on, the voltage at the drain of the second detection MOS transistor JM2 is as follows:

Visen＝Iload*JR3/KI；

wherein Visen represents a third sensed voltage indicative of the current flowing through the heating element 250, Iload represents the real-time current flowing through the heating element 250, KI: 1 represents the width-to-length ratio of the first switching unit 210 (first MOS transistor) to the first detection MOS transistor JM1, JR3 represents the resistance of the third detection resistor JR3, and the values of JR3 and KI are known. In this embodiment, the first switch unit 210, the first detection MOS transistor JM1, and the second detection MOS transistor JM2 are all PMOS transistors. However, the present application is not limited to this, and in other embodiments of the present application, all NMOS transistors and the like may be used.

In the present embodiment, when the first switch unit 210 is turned on, the first detection MOS transistor JM1 is also turned on, and the iioad current flows through the first switch unit 210, the iioad/KI current flows through the first detection MOS transistor JM1, and the current also flows through the third detection resistor JR3, the voltage Visen at the drain of the second detection MOS transistor JM2 with respect to the first ground GND1 is as above, when the first switch unit 210 is turned off, the first detection MOS transistor JM1 is also turned off, and the voltage Visen at the drain of the second detection MOS transistor JM2 is the voltage of the first ground GND1, and is generally 0V or microvolts. Therefore, whether the first switching unit 210 is operated or not can be directly judged by detecting the magnitude of the voltage Visen.

In this embodiment, the system control unit 220 further includes an overdriving protection unit 223, the overdriving protection unit 223 includes an overdriving comparison unit 410, the overdriving comparison unit 410 is generally a voltage comparator, one input terminal of the overdriving comparison unit 410 is electrically connected to the drain of the second detection MOS transistor JM2 to receive the detection voltage Visen, the other input terminal of the overdriving comparison unit 410 is connected to the first reference voltage Vref1, the first reference voltage Vref1 is greater than the voltage of the battery terminal BAT1 when the first switch unit 210 is disconnected, the first reference voltage Vref1 is less than the detection voltage when the first switch unit 210 is connected, and the range of the first reference voltage Vref1 is (0.5/K) V- (3.2/K) V, for example.

In this embodiment, the over-suction protection unit 223 includes an over-suction logic unit, which is described in the first embodiment to the fourth embodiment and is not described herein again.

In addition, in this embodiment, please refer to fig. 10, the branch detecting unit further includes a voltage division detecting unit, and the voltage division detecting unit and the current detecting unit may only have one of them. In this embodiment, the voltage division detecting unit includes a fourth detecting resistor JR4 and a fifth detecting resistor JR5, one end of the fourth detecting resistor JR4 is electrically connected to the atomization terminal AT, the other end of the fourth detecting resistor JR4 is electrically connected to one end of the fifth detecting resistor JR5, and the other end of the fifth detecting resistor JR5 is electrically connected to the first ground terminal GND 1. Here, the divided voltage Vvsen at the connection point of the fourth detection resistor JR4 and the fifth detection resistor JR5 may also be used to determine the second detection voltage, where the divided voltage is the second detection voltage.

Vvsen＝Vload*JR5/(JR3+JR4)；

Wherein Vvsen represents the divided voltage, Vload represents the voltage drop across the heating element 250, JR4 represents the resistance of the fourth sensing resistor JR4, and JR5 represents the resistance of the fifth sensing resistor JR 5. Here, the divided voltage Vvsen indirectly represents the voltage of the atomization end AT. So that whether the first switching unit 210 operates can be directly judged by dividing the voltage Vvsen.

Sixth embodiment

Referring to fig. 11, fig. 11 is a circuit block diagram of a system control circuit according to a sixth embodiment of the present application, which is similar to the fifth embodiment, so that the undescribed portion of the present embodiment can refer to the fifth embodiment, and the main difference between the present embodiment and the fifth embodiment is that the first switch unit 210 is disposed below.

Referring to fig. 5 and fig. 11, in the present embodiment, the first switch unit 210 is disposed below, and the system control module 272 includes a branch detection unit, where the branch detection unit is configured to obtain a second detection voltage, and the second detection voltage is used to represent whether the heating branch is turned on. In this embodiment, the branch detecting unit includes a current detecting unit and an atomization end AT, and the current detecting unit is configured to obtain a detection voltage proportional to a current flowing through the heating branch, where the detection voltage is used to determine a second detection voltage, and in this embodiment, the detection voltage is the second detection voltage, and the detection voltage is used to characterize whether a current flows in the heating branch.

Specifically, referring to fig. 5 and 11 in combination, in the present embodiment, the current detecting unit includes a first detecting MOS transistor JM1, a first detecting operational amplifier JOPA1, a second detecting MOS transistor JM2 and a third detecting resistor JR3, wherein a gate of the first detecting MOS transistor JM1 is electrically connected to the gate of the first switching unit 210, a drain of the first detecting MOS transistor JOPA is electrically connected to the first ground GND1, a source of the first detecting operational amplifier JOPA1 is electrically connected to the reverse terminal, a common terminal of the first detecting operational amplifier JOPA1 is electrically connected to the fogging terminal AT, the reverse terminal of the first detecting operational amplifier JOPA1 is also electrically connected to the drain of the second detecting MOS transistor jjjm 2, an output terminal of the first detecting operational amplifier JOPA1 is electrically connected to the gate of the second detecting MOS transistor JOPA 2, a source of the second detecting MOS transistor jjm 2 is electrically connected to one terminal of the third detecting resistor JR3, and another detecting resistor JR3 is electrically connected to the battery terminal 1. When the first switch unit 210 is turned on, the voltage at the source of the second detection MOS transistor JM2 is as follows:

Visen＝Vbat-Iload*JR3/KI；

wherein Visen represents a sensed voltage indicative of a current flowing through the heating element 250, Vbat represents a battery terminal BAT1 voltage, Iload represents a real-time current flowing through the heating element 250, KI: 1 represents the width-to-length ratio of the first switching unit 210 (first MOS) to the first sensing MOS transistor JM1, JR3 represents the resistance of the third sensing resistor JR3, and the values of JR3 and KI are known. In this embodiment, the first switch unit 210, the first detection MOS transistor JM1, and the second detection MOS transistor JM2 are all PMOS transistors. However, the present application is not limited to this, and in other embodiments of the present application, all NMOS transistors and the like may be used.

In this embodiment, when the first switch unit 210 is turned on, the first detection MOS transistor JM1 is also turned on, and at this time, the current Iload flows through the first switch unit 210, the Iload/KI current flows through the first detection MOS transistor JM1, and the current also flows through the third detection resistor JR3, and at this time, the voltage Visen at the source of the second detection MOS transistor JM2 is smaller as the above formula, and when the first switch unit 210 is turned off and turned off, the first detection MOS transistor JM1 is also turned off and turned off, and at this time, the voltage Visen at the source of the second detection MOS transistor JM2 is larger as the voltage of the battery terminal BAT 1. So that whether the first switching unit 210 operates can be directly judged by detecting the voltage Visen.

In this embodiment, the system control unit 220 further includes an overdriving protection unit 223, the overdriving protection unit 223 includes an overdriving comparison unit 410, the overdriving comparison unit 410 is generally a voltage comparator, one input terminal of the overdriving comparison unit 410 is electrically connected to the drain of the second detection MOS transistor JM2 to receive the detection voltage Visen, the other input terminal of the overdriving comparison unit 410 is connected to the second reference voltage Vref2, the second reference voltage Vref2 is smaller than the voltage of the battery terminal BAT1 when the first switch unit 210 is turned off, and the second reference voltage Vref2 is larger than the detection voltage when the first switch unit 210 is turned on.

In this embodiment, the over-suction protection unit 223 further includes an over-suction logic unit, which is described in the first embodiment to the fourth embodiment and is not described herein again.

In addition, in this embodiment, please refer to fig. 11, the branch detecting unit further includes a voltage division detecting unit, and the voltage division detecting unit and the current detecting unit may only have one of them. In this embodiment, the divided voltage detection unit includes a fourth detection resistor JR4 and a fifth detection resistor JR5, one end of the fourth detection resistor JR4 is electrically connected to the battery terminal BAT1, the other end of the fourth detection resistor JR4 is electrically connected to one end of the fifth detection resistor JR5, and the other end of the fifth detection resistor JR5 is electrically connected to the battery terminal BAT 1. Here, the divided voltage at the connection point of the fourth detection resistor JR4 and the fifth detection resistor JR5 may also be used to determine the second detection voltage, where the divided voltage is the second detection voltage.

Vvsen＝Vbat-Vload*JR5/(JR4+JR5)；

Wherein Vvsen represents the divided voltage, Vload represents the voltage drop across the heating element 250, JR4 represents the resistance of the fourth sensing resistor JR4, and JR5 represents the resistance of the fifth sensing resistor JR 5. Here, the divided voltage Vvsen indirectly represents the voltage of the atomization end AT. So that whether the first switching unit 210 operates can be directly judged by dividing the voltage Vvsen. In addition, the partial pressure detection unit and the current detection unit can also have other functions.

Seventh embodiment

In the first to sixth embodiments, whether the first switch unit 210 is turned on or off is determined by detecting the voltage of the atomization end AT, the voltage of the second detection resistor 271 and the current flowing through the heating element 250, but this embodiment is different from the previous embodiments in that the first switch unit 210 is turned on or off by detecting the driving voltage of the first switch unit 210. Parts not described in the present embodiment may be referred to in the first to sixth embodiments.

Generally, when the first switch unit 210 is PMOS (the present embodiment takes PMOS transistor as an example for illustration), the control terminal of the first switch unit 210 drives the first switch unit 210 to turn on through a lower voltage, such as the voltage of the first ground GND1, and the control terminal of the first switch unit 210 drives the first switch unit 210 to turn off through a higher voltage, such as the voltage of the battery terminal BAT 1. When the first switch unit 210 is an NMOS, at this time, the control terminal of the first switch unit 210 drives the first switch unit 210 to turn on through a higher voltage, for example, the voltage of the battery terminal BAT1, and the control terminal of the first switch unit 210 drives the first switch unit 210 to turn off through a lower voltage, for example, the voltage of the first ground terminal GND 1. Thus, the voltage that normally drives the first switching unit 210 to turn on or turn off is determined and the phase difference is relatively large.

In order to determine whether the first switch unit 210 is turned on or off, referring to fig. 12, in the present embodiment, the system control module 272 includes a branch detecting unit, where the branch detecting unit is configured to obtain a second detection voltage, and the second detection voltage is used to represent whether the heating branch is turned on. In the present embodiment, the branch detecting unit includes a control terminal of the first switching unit 210. In this embodiment, the system control unit 220 further includes an overdriving protection unit 223, the overdriving protection unit 223 is electrically connected to the control terminal of the first switch unit 210, the voltage of the control terminal of the first switch unit 210 is used to determine the second detection voltage, and in this embodiment, the voltage of the control terminal of the first switch unit 210 is the second detection voltage. Specifically, the overdraw protection unit 223 includes the overdraw comparison unit 410, the overdraw comparison unit 410 is, for example, a voltage comparator, one input terminal of the overdraw comparison unit 410 is electrically connected to the control terminal of the first switch unit 210, the other input terminal of the overdraw comparison unit 410 is electrically connected to the third reference voltage generation unit, the third reference voltage generation unit generates the second reference voltage Vref2 and inputs the second reference voltage to the overdraw comparison unit 410, in this embodiment, the second reference voltage Vref2 is generally between the turn-on voltage and the turn-off voltage of the first switch unit 210, for example, between 0.5V and 2V, for example, 0.5V, 1V, 1.5V, 2V, and the like, in this embodiment, when the first switch unit 210 is turned off and turned off, the voltage of the control terminal of the first switch unit 210 is greater than the second reference voltage Vref2, the overdraw comparison unit 410 outputs the second level signal, when the first switch unit 210 is turned on and turned on, at this time, the voltage of the control terminal of the first switching unit 210 is less than the second reference voltage Vref2, and the overdriving comparison unit 410 outputs the first level signal. In this embodiment, the first level signal is at a high level or a low level, and the second level signal is at a low level or a high level. In addition, in other embodiments of the present application, when the first switch unit 210 is an NMOS transistor, the other input terminal of the over-pull comparison unit 410 is connected to the first reference voltage Vref1, the first reference voltage Vref1 is generally between the turn-on voltage and the turn-off voltage of the first switch unit 210, for example, 0.5V-2V, for example, 0.5V, 1V, 1.5V, 2V, and the like, at this time, when the first switch unit 210 is turned off and off, the voltage of the control terminal of the first switch unit 210 is smaller than the first reference voltage Vref1, the over-pull comparison unit 410 outputs the second level signal, when the first switch unit 210 is turned on and off, the voltage of the control terminal of the first switch unit 210 is greater than the first reference voltage Vref1, and the over-pull comparison unit 410 outputs the first level signal.

In this embodiment, the over-suction protection unit 223 further includes an over-suction logic unit, which is described in the first to sixth embodiments and is not described herein again.

In addition, in the present embodiment, the first switch unit 210 is built-in, but the present application is not limited thereto, and in other embodiments of the present application, the first switch unit 210 may also be externally installed, in which case, the branch detection unit includes a first switch control terminal (pin) GT, the first switch control terminal GT is electrically connected to the control terminal of the first switch unit 210, and one input terminal of the over-suction comparison unit 410 is electrically connected to the first switch control terminal GT.

Eighth embodiment

In the first to seventh embodiments, the first switch unit 210 is prevented from being turned on for a long time by one over-suction protection unit, and in order to prevent the problem that one over-suction protection unit fails, the embodiment provides two different over-suction protection units to prevent the problem that the first switch unit 210 is turned on for a long time.

In this embodiment, two different over-suction protection units are respectively referred to as a first over-suction protection unit 222 and a second over-suction protection unit 223, where the first over-suction protection unit 222 is an over-suction protection unit in the prior art, and the second over-suction protection unit 223 is an over-suction protection unit in the first to seventh embodiments.

Referring to fig. 13a and 13b, in the present embodiment, the system control unit 220 includes a first over-suction protection unit 222 and a second over-suction protection unit 223, wherein the first over-suction protection unit 222 includes a first timing unit 460 and a first duration control unit 470, the first timing unit 460 and the first duration control unit 470 are respectively electrically connected to the airflow detection unit 281, the first duration control unit 470 is respectively electrically connected to the first timing unit 460 and the switch control unit 284, when the airflow detection unit 281 detects that the airflow flows greatly through the airflow detection element 240, for example, the airflow detection unit 281 detects that the airflow is small or large by detecting the conduction of a microphone switch, the change of microphone capacitance, and the like, the airflow detection unit 281 determines that the user is smoking, and at this time, the first timing unit 460 performs timing, and the switch control unit 284 drives the first switch unit 210 by the above method, the heating element works to realize the tobacco tar atomization effect. When the airflow detecting unit 281 detects that the airflow flow is small or no airflow flow through the airflow detecting element 240, the airflow detecting unit 281 judges that the user stops smoking or does not smoke, at this time, the first timing unit 460 stops timing, and the switch control unit 284 stops driving the first switch unit 210, and the first switch unit 210 keeps off. When the airflow detecting unit 281 detects that the airflow duration is longer or the false triggering time is longer through the airflow detecting element 240, and the first time duration control unit 470 determines that the time duration timed by the first timing unit 460 is greater than or equal to a first preset time duration, the first time duration control unit 470 outputs a turn-off signal to the switch control unit 284, the switch control unit 284 forcibly stops driving the first switch unit 210, and the first switch unit 210 keeps being turned off. In the present application, the first preset time period ranges from 4s to 15s, for example, 4s, 5s, 6s, 7s, 8s, 9s, 10s, 11s, 12s, 13s, 14s, 15s, and the like. In this embodiment, the first timing unit 460 and the first time length control unit 470 may be implemented in a single circuit module, or may be implemented separately.

In this embodiment, the second over-suction protection unit 223 may be any one of the over-suction protection units in the first to seventh embodiments, and is not described herein again. In this embodiment, the first preset time period and the second preset time period are equal in time, or the time difference between the first preset time period and the second preset time period is within 10%.

In this embodiment, the switch control unit 284 includes a logic gate circuit, which is, for example, an and gate in this embodiment, three input terminals of the and gate are electrically connected to the first and second

over-suction protection units

222 and 223 and the airflow detection unit 281, respectively, and an output terminal of the and gate is electrically connected to other circuit units in the switch control unit 284. The airflow detection unit 281 is electrically connected with the first over-suction protection unit 222 and the second over-suction protection unit 223 respectively, the airflow detection unit 281 is electrically connected with the second over-suction protection unit 223 and is mainly used for sending a reset signal to the second over-suction protection unit 223, and the airflow detection unit 281 is electrically connected with the first over-suction protection unit 222 and is mainly used for triggering the first timing unit 460 to start timing and triggering the first timing unit 460 to reset.

In the present embodiment, regardless of whether the first and second

overabsorption protection units

222 and 223 are triggered to generate overabsorption protection, when the airflow detection unit 281 detects a change from airflow to no airflow or from no airflow to airflow, since the airflow detection unit 281 is electrically connected to the first and second

overabsorption protection units

222 and 223, respectively, it triggers resetting of the first and second

duration control units

470 and 430, that is, the first and second

duration control units

470 and 430 are reset by edge triggering (reset signal), for example, the first and second

duration control units

470 and 430 are reset by rising edge or falling edge triggering, and the first and second

duration control units

470 and 430 are restored to normal state. In the normal state, the first duration control unit 470 and the second duration control unit 430 output turn-on signals to the switch control unit 284, and at this time, the two input ends of the and gate receive turn-on signals. When the airflow detecting unit 281 outputs the turn-on signal to the switch control unit 284 and the first timing unit 460, the first timing unit 460 starts timing again, and since the three input terminals of the switch control unit 284 receive the turn-on signal, the switch control unit 284 controls the first switch unit 210 to turn on, and the second timing unit starts timing. The design can prevent the over-suction and does not influence the normal use of the user.

It should be understood that reference to "a plurality" herein means two or more. Other embodiments of the present application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the application being indicated by the following claims.

It should be noted that, in the present specification, the embodiments are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments may be referred to each other. For the device embodiment, since it is basically similar to the method embodiment, the description is simple, and for the relevant points, refer to the partial description of the method embodiment.

The above disclosure is only for the purpose of illustrating the preferred embodiments of the present application and is not to be construed as limiting the scope of the present application, so that the present application is not limited thereto, and all equivalent variations and modifications can be made to the present application.

Claims

1. The system control circuit applied to the electronic cigarette is characterized by comprising a system control module and a first switch unit, wherein the system control module comprises a battery end, a first grounding end and a system control unit, the battery end and the first grounding end are correspondingly and electrically connected with two ends of a battery assembly, the system control unit comprises a switch control unit, the switch control unit is electrically connected with a control end of the first switch unit, and the first switch unit is used for being connected with a heating element in series to form at least part of heating branches;

2. The system control circuit according to claim 1, wherein the branch detection unit comprises an atomization end, the atomization end is electrically connected with one end of the first switch unit, the atomization end is further used for being electrically connected with one end of the heating element, and the second detection voltage is determined according to a voltage of the atomization end.

3. The system control circuit according to claim 2, wherein the second detection voltage is a voltage of the atomization end, when the second over-suction protection unit determines that the second detection voltage is greater than a preset first reference voltage or less than a preset second reference voltage, the second over-suction protection unit starts timing, and when a timing duration of the second over-suction protection unit is greater than or equal to a second preset duration, the second over-suction protection unit controls the first switch unit to keep off through a switch control unit.

4. The system control circuit according to claim 2, wherein the branch detection unit further includes a current detection unit electrically connected to the atomizing terminal, the current detection unit being configured to obtain a third detection voltage proportional to a current flowing through the heat generating branch, the second detection voltage being determined according to the third detection voltage.

5. The system control circuit according to claim 4, wherein one end of the first switch unit is electrically connected to the battery terminal, and the other end of the first switch unit is electrically connected to the atomizing terminal; the second detection voltage is the third detection voltage, the current detection unit comprises a first detection MOS tube, a first detection operational amplifier, a second detection MOS tube and a third detection resistor, wherein, the grid electrode of the first detection MOS tube is electrically connected with the grid electrode of the first switch unit, the source electrode of the first detection MOS tube is electrically connected with the battery end, the drain electrode of the first detection operational amplifier is electrically connected with the same-direction end of the first detection operational amplifier, the reverse end of the first detection operational amplifier is electrically connected with the atomization end, the same-direction end of the first detection operational amplifier is also electrically connected with the source electrode of the second detection MOS tube, the output end of the first detection operational amplifier is electrically connected with the grid electrode of the second detection MOS tube, the drain electrode of the second detection MOS tube is electrically connected with one end of a third detection resistor, the other end of the third detection resistor is connected with the first grounding end, and the third detection voltage is the voltage at the drain electrode of the second detection MOS tube; alternatively, the first and second electrodes may be,

6. The system control circuit according to claim 2, wherein the branch detection unit further includes a voltage division detection unit, the voltage division detection unit is electrically connected to the atomization end, the voltage division detection unit is configured to obtain a divided voltage proportional to a voltage drop of the heating element, and the second detection voltage is determined according to the divided voltage.

7. The system control circuit according to claim 6, wherein one end of the first switch unit is electrically connected to the battery terminal, and the other end of the first switch unit is electrically connected to the atomizing terminal; the second detection voltage is equal to the divided voltage, the divided voltage detection unit comprises a fourth detection resistor and a fifth detection resistor, one end of the fourth detection resistor is electrically connected with the atomization end, the other end of the fourth detection resistor is electrically connected with one end of the fifth detection resistor, the other end of the fifth detection resistor is electrically connected with the first grounding end, and the divided voltage is the voltage at the connection point of the fourth detection resistor and the fifth detection resistor; alternatively, the first and second electrodes may be,

8. The system control circuit according to claim 1, wherein the branch detecting unit includes a control terminal of the first switching unit, and the second detection voltage is determined according to a voltage of the control terminal of the first switching unit.

9. The system control circuit according to claim 8, wherein the second detection voltage is a voltage of a control terminal of the first switch unit, when the second over-suction protection unit determines that the second detection voltage is greater than a first reference voltage or less than a second reference voltage, the second over-suction protection unit starts timing, and when a timing duration of the second over-suction protection unit is greater than or equal to a second preset duration, the second over-suction protection unit controls the first switch unit to keep off through a switch control unit.

10. The system control circuit according to claim 1, wherein the heating branch circuit includes a first switch unit, a heating element and a second detection resistor connected in series, the branch circuit detection unit includes a heating detection terminal for being electrically connected to a detection connection point, the detection connection point is a connection point of the first switch unit and the second detection resistor or a connection point of the heating element and the second detection resistor, and the second detection voltage is determined according to a voltage of the heating detection terminal.

11. The system control circuit according to claim 10, wherein the second detection voltage is a voltage of the heat generation detection terminal, when the second overdriving protection unit determines that the second detection voltage is greater than a first reference voltage or less than a second reference voltage, the second overdriving protection unit starts to time, and when a time duration of the second overdriving protection unit is greater than or equal to a second preset time duration, the second overdriving protection unit controls the first switch unit to keep off through a switch control unit.

12. The system control circuit according to any one of claims 1 to 11, wherein the second overdriving protection unit includes an overdriving comparison unit and an overdriving logic unit, one input terminal of the overdriving comparison unit is connected to a second detection voltage, the other input terminal of the overdriving comparison unit is connected to a preset first reference voltage or a preset second reference voltage, the output terminal of the overdriving comparison unit is electrically connected to the overdriving logic unit, and the overdriving logic unit is electrically connected to the switch control unit.

13. The system control circuit of claim 12, wherein the overdraw logic unit includes a second timing unit and a second duration control unit, the input end of the second timing unit is electrically connected with the over-suction comparison unit, the output end of the second timing unit is electrically connected with the second duration control unit, when the over-suction comparison unit judges that the second detection voltage is greater than the first reference voltage or less than the second reference voltage, the second timing unit starts timing, when the over-suction comparison unit judges that the second detection voltage is smaller than the first reference voltage or larger than the second reference voltage, the second timing unit stops timing, when the second time length control unit judges that the timing time length of the second timing unit is greater than or equal to a second preset time length, the second time length control unit outputs an over-suction protection signal to control the first switch unit to be kept disconnected.

14. The system control circuit according to claim 13, wherein the second timing unit includes a first reference frequency generation unit and a second timing subunit; the second timing subunit is respectively and electrically connected with the over-suction comparison unit, the second duration control unit and the first reference frequency generation unit, starts timing when the over-suction comparison unit judges that the second detection voltage is greater than a first reference voltage or less than a second reference voltage, and stops timing when the over-suction comparison unit judges that the second detection voltage is less than the first reference voltage or greater than the second reference voltage; alternatively, the first and second electrodes may be,

the second timing unit comprises a second reference frequency generation unit and a second timing subunit; the second reference frequency generation unit is electrically connected with the over-suction comparison unit, the second timing subunit is respectively electrically connected with the second duration control unit and the second reference frequency generation unit, when the over-suction comparison unit judges that the second detection voltage is greater than the first reference voltage or less than the second reference voltage, the second reference frequency generation unit starts to work, and when the over-suction comparison unit judges that the second detection voltage is less than the first reference voltage or greater than the second reference voltage, the second reference frequency generation unit stops working.

15. The system control circuit according to claim 12, wherein the overdriving logic unit comprises a second timing unit, a second duration control unit, a third timing unit and a third duration control unit, an input terminal of the second timing unit and an input terminal of the third timing unit are respectively electrically connected to the overdriving comparison unit, the second timing unit is electrically connected to the second duration control unit, the third timing unit is electrically connected to the third duration control unit, the third duration control unit is electrically connected to the second timing unit, the second timing unit starts to time when the overdriving comparison unit determines that the second detection voltage is greater than a first reference voltage or less than a second reference voltage, the third timing unit starts to time when the overdriving comparison unit determines that the second detection voltage is less than the first reference voltage or greater than the second reference voltage, when the over-suction comparison unit judges that the second detection voltage is greater than the first reference voltage or less than the second reference voltage, the third timing unit stops timing, when the third duration control unit judges that the timing duration of the third timing unit is greater than or equal to a third preset duration, a reset signal is output to the second timing unit so that the second timing unit stops timing and sets the timing duration to zero, and when the second duration control unit judges that the timing duration of the second timing unit is greater than or equal to the second preset duration, the second over-suction protection unit is used for controlling the first switch unit to be kept disconnected.

16. The system control circuit of claim 15, wherein the second timing unit comprises a first reference frequency generation unit and a second timing subunit, and the third timing unit comprises a third timing subunit; wherein the second timing subunit is respectively electrically connected with the over-suction comparison unit, the second duration control unit and the first reference frequency generation unit, the third timing subunit is respectively electrically connected with the over-suction comparison unit, the third duration control unit and the first reference frequency generation unit, the third duration control unit is electrically connected with the second timing subunit, the second timing subunit starts timing when the over-suction comparison unit judges that the second detection voltage is greater than the first reference voltage or less than the second reference voltage, the third timing subunit starts timing when the over-suction comparison unit judges that the second detection voltage is less than the first reference voltage or greater than the second reference voltage, and the third timing subunit stops timing when the over-suction comparison unit judges that the second detection voltage is greater than the first reference voltage or less than the second reference voltage, when the third time length control unit judges that the timing time length of the third timing subunit is greater than or equal to a third preset time length, a reset signal is output to the second timing subunit so that the second timing unit stops timing and the timing time length is set to zero; alternatively, the first and second electrodes may be,

17. The system control circuit according to any one of claims 1 to 11, wherein the system control unit comprises an airflow detection unit, the airflow detection unit is configured to be electrically connected to an airflow detection element, and the airflow detection unit is further electrically connected to the second over-suction protection unit;

when the timing duration of the second over-suction protection unit is greater than or equal to a second preset duration, the second over-suction protection unit locks and outputs an over-suction protection signal to the switch control unit so that the first switch unit is kept disconnected, and the airflow detection unit triggers the second over-suction protection unit to unlock through an edge signal so that the second over-suction protection unit outputs a turn-on signal to the switch control unit.

18. The system control circuit according to claim 17, wherein the switch control unit includes a logic gate circuit, one input terminal of the logic gate circuit is electrically connected to the airflow detection unit, the other input terminal of the logic gate circuit is electrically connected to a second overdraw protection unit, the switch control unit controls the first switch unit to operate when both the airflow detection unit and the second overdraw protection unit output on-signals, and the first switch unit stops operating when at least one of the airflow detection unit and the second overdraw protection unit outputs off-signals.

19. The system control circuit according to any of claims 1-11, wherein the second predetermined duration is adjustable.

20. The system control circuit according to claim 19, wherein the second over-suction protection unit comprises a first reference frequency generation unit or a second reference frequency generation unit, wherein the first reference frequency generation unit or the second reference frequency generation unit comprises a frequency comparator, a frequency switch unit, a first current source and a frequency capacitor, wherein a first end of the first current source is electrically connected to the battery terminal, a second end of the first current source is electrically connected to the first end of the frequency switch unit, an input end of the frequency comparator and the frequency capacitor terminal, respectively, another input end of the frequency comparator is connected to a preset first frequency reference voltage, an output end of the frequency comparator is electrically connected to the control terminal of the frequency switch unit, a second end of the frequency switch unit is electrically connected to the first ground terminal, and the frequency capacitor terminal is used for being electrically connected to the frequency capacitor, the second preset time is used for being in a proportional relation with the capacitance value of the frequency capacitor; alternatively, the first and second electrodes may be,

21. The system control circuit according to any one of claims 1 to 11, wherein the system control module and the first switch unit are located on a same chip, the battery terminal is a battery pin, and the first ground terminal is a first ground pin; alternatively, the first and second electrodes may be,

22. An electronic cigarette, comprising:

a battery assembly including a battery;

the atomization assembly, which comprises the system control circuit as claimed in any one of claims 1 to 21, and further comprises a heating element, the battery terminal and the first ground terminal of the system control circuit are electrically connected to the two terminals of the battery assembly, the first switch unit of the system control circuit is connected in series with the heating element to form at least part of a heating branch circuit, the heating branch circuit is connected in parallel with the system control module to form a parallel circuit, and the parallel circuit is electrically connected to the battery assembly.

23. The electronic cigarette of claim 22, wherein the system control module comprises an airflow detection end, the airflow detection end is used for being electrically connected with an airflow detection element, the system control unit comprises an airflow detection unit, the system control unit further comprises a first over-suction protection unit, the first over-suction protection unit comprises a first timing unit and a first time length control unit, the airflow detection unit is electrically connected with the airflow detection end, the first timing unit, the first time length control unit and the switch control unit respectively, and the first time length control unit is electrically connected with the switch control unit and the first timing unit respectively; when the airflow detection unit detects airflow flowing through the airflow detection element, the first timing unit starts timing, the switch control unit drives the first switch unit to work, when the airflow detection unit does not detect airflow flowing through the airflow detection element, the first timing unit stops timing and sets to zero, the switch control unit stops driving the first switch unit to stop working, when the timing duration of the first timing unit is greater than or equal to a first preset duration, the first time duration control unit locks and outputs an over-suction protection signal to the switch control unit so that the first switch unit is kept disconnected, and the airflow detection unit triggers the first time duration control unit to unlock through an edge signal so that the first over-suction protection unit outputs a starting and conducting signal to the switch control unit.

24. The electronic cigarette of claim 23, wherein the first predetermined period of time is equal to the second predetermined period of time.

25. The electronic cigarette according to any one of claims 22-24, wherein the switch control unit drives the first switch unit to operate in a PWM mode or a PFM mode, or drives the first switch unit to operate in a normally open conducting mode.