EP4678039A1

EP4678039A1 - Aerosol generating apparatus and control method therefor

Info

Publication number: EP4678039A1
Application number: EP24777888.9A
Authority: EP
Inventors: Jun Zhang; Zhongli XU; Yonghai LI
Original assignee: Shenzhen FirstUnion Technology Co Ltd
Current assignee: Shenzhen FirstUnion Technology Co Ltd
Priority date: 2023-03-24
Filing date: 2024-03-22
Publication date: 2026-01-14
Also published as: CN118680339A; WO2024199099A1

Abstract

An aerosol generating device and a control method therefor are provided, including: a battery core (20); a heating element (10), electrically connected to the battery core (20) to form a heating circuit; a sampling resistor (R1), electrically connected to the battery core (20) and the heating element (10) to form a sampling circuit; a switch transistor (Q1), configured to turn on or turn off the heating circuit and/or the sampling circuit; an analog-to-digital converter (ADC), configured to sample an electrical parameter of the sampling circuit; and a controller (31), configured to externally output a pulse signal for driving the switch transistor (Q1), to control a heating operation of the heating element (10), and further configured to generate an interrupt request and respond to the interrupt request to obtain the electrical parameter sampled by the ADC. The electrical parameter is accurately and effectively sampled through a high-frequency switch signal, to avoid a problem of the aerosol generating device generating noise as a result of a low-frequency switch signal being introduced into a circuit, thereby improving user experience.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Chinese Patent Application No. 202310340547.5, filed with the China National Intellectual Property Administration on March 24, 2023 and entitled "AEROSOL GENERATING DEVICE AND CONTROL METHOD THEREFOR", which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

Embodiments of this application relate to the field of electronic atomization technologies, and in particular, to an aerosol generating device and a control method therefor.

BACKGROUND

As an exemplary aerosol generating device, the device releases compounds by heating materials rather than burning materials. For example, the materials may be tobacco or another non-tobacco product, where the non-tobacco products may or may not include nicotine. As another exemplary aerosol generating device, the device usually include liquid. The liquid is heated to be atomized by the heating element, so as to generate an inhalable aerosol. The liquid may include nicotine and/or aromatics and/or aerosol-generation substances (such as glycerin).
In the foregoing device, an operating temperature of a heating element is usually determined by calculating a resistance value of a resistor which has a temperature coefficient. Before the calculation, an electrical parameter in a circuit needs to be detected, for example, voltage across a sampling resistor.
In the prior art, the voltage across the sampling resistor is usually detected by controlling turning on or turning off of different switches, so as to turn on a detection circuit and turn off a heating circuit. A problem with the manner is that a low-frequency switch signal is easily introduced into a circuit (a frequency of a switch signal in the heating circuit is much greater than a frequency of a switch signal in the detection circuit), which easily causes the aerosol generating device to generate noise and reduce user experience.

SUMMARY

This application provides an aerosol generating device and a control method therefor, so as to prevent the aerosol generating device from generating noise while sampling an electrical parameter in a circuit under a high-frequency switch signal.
An aspect of this application provides an aerosol generating device, including:

a battery core, configured to provide electric power;
a heating element, electrically connected to the battery core to form a heating circuit, where the heating element is configured to heat an aerosol forming substrate to generate an aerosol, and a resistance value of the heating element is changeable with a change of a heating temperature;
a sampling resistor, electrically connected to the battery core and the heating element to form a sampling circuit;
a switch transistor, configured to turn on or turn off the heating circuit and/or the sampling circuit;
an analog-to-digital converter (ADC), configured to sample an electrical parameter of the sampling circuit; and
a controller, configured to externally output a pulse signal for driving the switch transistor, to control a heating operation of the heating element, and further configured to generate an interrupt request and respond to the interrupt request to obtain the electrical parameter sampled by the ADC.

Another aspect of this application provides a control method for an aerosol generating device. The aerosol generating device includes:

a battery core, configured to provide electric power;
a heating element, electrically connected to the battery core to form a heating circuit, where the heating element is configured to heat an aerosol forming substrate to generate an aerosol, and a resistance value of the heating element is changeable with a change of a heating temperature;
a sampling resistor, electrically connected to the battery core and the heating element to form a sampling circuit;
a switch transistor, configured to turn on or turn off the heating circuit and/or the sampling circuit;
an ADC, configured to sample an electrical parameter of the sampling circuit; and
the control method includes:
externally outputting a pulse signal for driving the switch transistor, to control a heating operation of the heating element, and further configured to generate an interrupt request and respond to the interrupt request to obtain the electrical parameter sampled by the ADC.

In the foregoing aerosol generating device and the control method therefor, when the heating operation of the heating element is controlled, the electrical parameter sampled by the ADC can be periodically obtained by generating the interrupt request and responding to the interrupt request. In this way, the electrical parameter is sampled under a high-frequency switch signal, and the electrical parameter is collected accurately and effectively, to avoid a problem of the aerosol generating device generating noise as a result of a low-frequency switch signal being introduced into a circuit, thereby improving user experience.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments are illustratively described with reference to the figures in the corresponding accompanying drawings, and these illustrative descriptions are not to limit the embodiments. Elements having same reference numerals in the accompanying drawings are denoted as similar elements, and the figures in the accompanying drawings are not drawn to scale, unless particularly stated otherwise.

FIG. 1 is a schematic diagram of an aerosol generating device according to an embodiment of this application.
FIG. 2 is a schematic diagram of another aerosol generating device according to an embodiment of this application.
FIG. 3 is a schematic diagram of basic components of an embodiment of a circuit according to an embodiment of this application.
FIG. 4 is a schematic diagram of basic components of another embodiment of a circuit according to an embodiment of this application.
FIG. 5 is a schematic diagram of a process for generating a pulse-width modulation (PWM) pulse signal according to an embodiment of this application.
FIG. 6 is a schematic diagram of another process for generating a PWM pulse signal according to an embodiment of this application.
FIG. 7 is a schematic diagram of yet another process for generating a PWM pulse signal according to an embodiment of this application.

DETAILED DESCRIPTION

For ease of understanding of this application, this application is described below in more detail with reference to accompanying drawings and specific implementations.
FIG. 1 is a schematic diagram of an aerosol generating device according to an implementation of this application.
As shown in FIG. 1, the aerosol generating device includes:

a chamber A, where an aerosol generating article B is removably accommodated in a chamber A, and the aerosol generating article B contains a solid aerosol forming substrate;
a heating element 10, where when the aerosol generating article B is accommodated in the chamber A, the heating element 10 may be inserted into the aerosol generating article B for heating to generate an aerosol;
a battery core 20, configured to provide power; and
a circuit 30, arranged between the battery core 20 and the heating element 10. The circuit 30 is configured to control the aerosol generating device, for example, control the battery core 20 to provide electric power to the heating element 10.

The aerosol generating article B is preferably made of a tobacco-containing material that releases a volatile compound from a substrate when being heated, or may be a non-tobacco material adapted for electric heating and generating smoke after being heated. The aerosol generating article B is preferably made of a solid substrate. The solid substrate may include one or more of powders, particles, fragment strips, stripes, or flakes of one or more of vanilla leaves, tobacco leaves, homogeneous tobacco, and expanded tobacco. Alternatively, the solid substrate may include additional tobacco or non-tobacco volatile aroma compounds to be released when the substrate is heated.
It should be noted that heating methods of the heating element 10 include, but are not limited to, resistance heating, electromagnetic heating, and infrared heating. A shape of the heating element 10 includes, but is not limited to, a needle, a pin, or a sheet.
It should further be noted that, unlike the example of FIG. 1, in another example, it is also feasible that the heating element 10 is constructed to heat around at least part of the aerosol generating article B, which is commonly referred to as circumferential heating, peripheral heating, or the like.
FIG. 2 is a schematic diagram of another aerosol generating device according to an implementation of this application.
As shown in FIG. 2, the aerosol generating device includes an atomizer 100 configured to store a liquid aerosol forming substrate and heat and atomize the liquid aerosol forming substrate to generate an aerosol and a power supply device 200 configured to provide power to the atomizer 100.
In an optional implementation solution, for example, as shown in FIG. 2, the power supply device 200 includes a receiving cavity 270 arranged at one end along a length direction and configured to receive and accommodate at least part of the atomizer 100. The power supply device 200 further includes a first electrical contact 230 that is at least partially exposed on a surface of the receiving cavity 270, which is configured to form an electrical connection with the atomizer 100 to provide power to the atomizer 100 when at least part of the atomizer 100 is received and accommodated in the power supply device 200.
According to a preferred implementation solution shown in FIG. 2, an end portion of the atomizer 100 opposite to the power supply device 200 along the length direction is provided with a second electrical contact 104, so that when the at least part of the atomizer 100 is accommodated in the receiving cavity 270, the second electrical contact 104 is in contact with and abuts against the first electrical contact 230 to form an electrical connection.
The power supply device 200 is therein provided with a seal member 260. At least part of an internal space of the power supply device 200 is separated by the seal member 260 to form the receiving cavity 270. In the preferred implementation solution shown in FIG. 2, the seal member 260 is configured to extend along a cross section direction of the power supply device 200, and is preferably prepared by a flexible material such as silica gel, so as to prevent the aerosol forming substrate seeping from the atomizer 100 to the receiving cavity 270 from flowing to components such as a circuit 220 and an airflow sensor 250 inside the power supply device 200.
In the preferred implementation shown in FIG. 2, the power supply device 200 further includes a battery core 210 configured to provide power and facing away from the receiving cavity 270 along the length direction.
The power supply device 200 further includes the circuit 220. The circuit 220 operably directs a current between the battery core 210 and the first electrical contact 230.
The power supply device 200 further includes the airflow sensor 250 configured to sense an inhalation airflow generated during inhalation of the atomizer 100 by a user, so that the circuit 220 controls, based on a sense signal of the airflow sensor 250, the battery core 210 to output electric power to the atomizer 100.
Further, in the preferred implementation shown in FIG. 2, a charging interface 240 is arranged on an other end of the power supply device 200 facing away from the receiving cavity 270, and is configured to provide power to the battery core 210.
In an optional embodiment, for example, in the embodiment shown in FIG. 2, the atomizer 100 includes:

a liquid storage cavity 101, configured to store a liquid aerosol forming substrate;
a heating element 103, configured to heat and atomize the liquid aerosol forming substrate to generate an aerosol; and
a liquid guide element 102, configured to transfer the liquid aerosol forming substrate between the liquid storage cavity 101 and the heating element 103.

In an optional embodiment, the liquid aerosol forming substrate preferably includes a tobacco-containing material. The tobacco-containing material includes a volatile tobacco aroma compound released from the liquid aerosol forming substrate when being heated. Alternatively or additionally, the liquid aerosol forming substrate may include a non-tobacco material. The liquid aerosol forming substrate may water, ethanol or another solvent, a plant extract, a nicotine solution, and a natural flavoring agent or an artificial flavoring agent. Preferably, the liquid aerosol forming substrate further includes an aerosol forming agent. An example of a suitable aerosol forming agent includes glycerin and/or propylene glycol.
In the embodiment shown in FIG. 2, the liquid guide element 102 is constructed in a shape of a hollow columnar extending along a longitudinal direction of the atomizer 100, and the heating element 103 is formed in a cylindrical hollow of the liquid guide element 102. During use, as indicated by an arrow R1, the liquid aerosol forming substrate in the liquid storage cavity 101 is absorbed along an outer surface of the liquid guide element 102 in a radial direction, and then transferred to the heating element 103 on an inner surface to be heated and vaporized to generate an aerosol. The generated aerosol is outputted along a longitudinal direction of the atomizer 100 from the cylindrical hollow of the liquid guide element 102, as indicated by an arrow R2 in FIG. 1.
In another variant implementation, the liquid guide element 102 includes flexible fibers such as cotton fibers, non-woven fabrics, and glass fiber ropes, or includes porous ceramics with a microporous structure. In a specific implementation, a structure of the liquid guide element 102 using the porous ceramics may be in any of various regular or irregular shapes, for example, a shape described in patent CN212590248U .
In some embodiments, the heating element 103 has a structure such as a heating wire or a heating sheet, and is coupled to the liquid guide element 102 through contact. Alternatively, in another variant implementation, the heating element 103 may be coupled to the liquid guide element 102 through printing, deposition, sintering, physical assembly, or the like. In some other variant implementations, the liquid guide element 102 using the porous ceramics may have a plane or curved surface for supporting the heating element 103, and the heating element 103 is formed on the plane or the curved surface of the liquid guide element 102 through mounting, printing, deposition, or the like.
The heating element 103 may be made of a metal material with an appropriate impedance, a metal alloy, graphite, carbon, conductive ceramic, or another composite material of a ceramic material and a metal material. A suitable metal or alloy material includes at least one of nickel, cobalt, zirconium, titanium, nickel alloy, cobalt alloy, zirconium alloy, titanium alloy, nickel-chromium alloy, nickel-iron alloy, iron-chromium alloy, iron-chromium-aluminum alloy, titanium alloy, iron-manganese-aluminum based alloy, or stainless steel.
Based on the aerosol generating device shown in FIG. 1 and FIG. 2, a temperature of the heating element needs to be monitored during heating the aerosol forming substrate, so as to control the battery core to provide electric power to the heating element, thereby causing a user to obtain a better experience.
In an implementation, the heating element may be configured not only to heat the aerosol forming substrate, but also configured as a thermosensitive element for sensing a real-time temperature. For example, a resistive material of the heating element may select a metal or alloy material having a suitable resistance temperature coefficient, such as a positive temperature coefficient or a negative temperature coefficient, so that the heating element can be configured to generate heat and can be configured as a sensor for sensing a real-time temperature of the heating element.
For ease of illustration, the following example illustrates that the heating element may be configured not only to heat the aerosol forming substrate, but also configured as a thermosensitive element for sensing a real-time temperature.
FIG. 3 is a schematic diagram of basic components of an embodiment of a circuit.
As shown in FIG. 3, the circuit includes a switch transistor Q1, a sampling resistor R1, and a heating element (R2 shown in the figure) connected in series. Specifically,
the switch transistor Q1 has one electrode terminal electrically connected to a battery core (VCC shown in the figure), an other electrode terminal electrically connected to the sampling resistor R1, and a control terminal electrically connected to a first port (for example, an IO port shown in the figure) of a controller, so as to receive a drive signal generated by the controller, thereby being turned off or turned on. The controller includes, but is not limited to, a microcontroller unit (MCU). When the switch transistor Q1 is turned on, the battery core provides electric power to the heating element. The switch transistor Q1 includes, but is not limited to, a metal-oxide-semiconductor (MOS) transistor, an insulated gate bipolar transistor (IGBT) transistor, or the like.
The sampling resistor R1 is positioned between the switch transistor Q1 and the heating element (R2 shown in the figure). The sampling resistor R1 is a standard resistor with a substantially constant resistance value, and a resistance value of the sampling resistor R1 is much smaller than a resistance value of the heating element, so as to prevent the sampling resistor R1 from consuming excessive energy. Generally, the resistance value is in a range of 0.1 mΩ to 0.1 Ω.
As can be seen from the above figure, a heating circuit is formed by the heating element and the battery core, and a sampling circuit is formed by the sampling resistor R1 together with the heating element and the battery core. The heating circuit and the sampling circuit are actually a same circuit. It should be noted that a series connection mode of the switch transistor Q1, the sampling resistor R1, and the heating element is not limited to the situation shown in the figure.
One input terminal (a reference number 1 shown in the figure) of an operational amplifier U1 is electrically connected to one end of the sampling resistor R1, and an other input terminal (a reference number 2 shown in the figure) of the operational amplifier U1 is electrically connected to an other end of the sampling resistor R1, namely, electrically connected between the sampling resistor R1 and the heating element. An output terminal (a reference number 3 shown in the figure) of the operational amplifier U1 is electrically connected to a second port (for example, an analog-to-digital converter (ADC) port shown in the figure) of the controller, so as to feed back a voltage value across the sampling resistor R1 to an ADC of the controller.
In a preferred implementation, the ADC is integrated in the controller and electrically connected to the operational amplifier U1 through a port of the ADC. Certainly, in another example, the ADC may also be arranged outside the controller.
A voltage across the sampling resistor R1 is denoted as V1, and a voltage across the heating element is denoted as V2. It is assumed that a resistance value of the sampling resistor R1 is R1, and a resistance value of the heating element is R2. Because the V1, V2, and R1 are all known, the resistance value of the heating element can be calculated by the following equation: $R 2 = \frac{V 2}{V 1} * R 1$ . Then, a corresponding temperature of the heating element can be calculated based on a relevant equation of a resistance temperature coefficient.
FIG. 4 is a schematic diagram of basic components of another embodiment of a circuit.
As shown in FIG. 4, the circuit includes a switch transistor and a sampling resistor R1. The switch transistor includes a first switch transistor Q1 and a second switch transistor Q2. R2 in the figure is a heating element having a resistance temperature coefficient. The first switch transistor Q1 and the heating element are connected to form a heating circuit. The second switch transistor Q2, the sampling resistor R1, and the heating element are connected to form a sampling circuit. Specifically,
the first switch transistor Q1 has one electrode terminal electrically connected to a battery core (VCC shown in the figure), an other electrode terminal electrically connected to one end of the heating element, and a control terminal electrically connected to a first port (for example, an IO port 1 shown in the figure) of the controller, so as to receive a control signal of the controller, thereby turning off or turning on the heating circuit. An other end of the heating element is grounded.
The second switch transistor Q2 has one electrode terminal electrically connected to the battery core (VCC shown in the figure), an other electrode terminal electrically connected to one end of the sampling resistor R1, and a control terminal electrically connected to a second port (for example, an IO port 2 shown in the figure) of the controller, so as to receive a control signal of the controller, thereby turning off or turning on the sampling circuit. An other end of the sampling resistor R1 is electrically connected to one end of the heating element.
The first switch transistor Q1 and the second switch transistor Q2 include, but are not limited to, an MOS transistor, an IGBT transistor, or the like.
Generally, the first switch transistor Q1 and the second switch transistor Q2 are configured not to be turned on simultaneously. When the first switch transistor Q1 is turned on and the second switch transistor Q2 is turned off, the battery core provides electric power to the heating element. When the first switch transistor Q1 is turned off and the second switch transistor Q2 is turned on, the controller may sample a voltage at a point a in the figure through a third port (for example, an ADC1 port shown in the figure), and may sample a voltage at a point b in the figure through a fourth port (for example, an ADC2 port shown in the figure). It may be understood that when the voltages at the point a and the point b are sampled in the figure, the voltage at the point a or the point b in the figure may first be divided through a voltage division circuit, and then be sampled through the controller.
A voltage of the battery core (that is, a voltage at the point a) is denoted as Va, and a voltage across the heating element (that is, a voltage at the point b) is denoted as Vb. It is assumed that a resistance value of the sampling resistor R1 is R1, and a resistance value of the heating element is R2. Because Va, Vb, and R1 are all known, the resistance value of the heating element can be calculated by the following equation: $R 2 = \frac{Vb}{Va - Vb} * R 1$ . Then, a corresponding temperature of the heating element can be calculated based on a relevant equation of a resistance temperature coefficient.
It should be noted that the above calculation of the resistance value or the temperature of the heating element by measuring the voltage is not limited to the situations of shown in FIG. 3 and FIG. 4.
In an example, the controller is configured to externally output a pulse signal for driving the switch transistor, to control a heating operation of the heating element, and further configured to generate an interrupt request and respond to the interrupt request to obtain the electrical parameter sampled by the ADC.
In this example, a frequency of the pulse signal can be increased, to prevent the circuit from generating noise at a lower frequency. Generally, the frequency of the pulse signal is above 10 kHz; preferably, the frequency of the pulse signal is above 12 kHz; further preferably, the frequency of the pulse signal is above 14 kHz; further preferably, the frequency of the pulse signal is above 16 kHz; and further preferably, the frequency of the pulse signal is above 20 kHz. An upper limit value of the frequency of the pulse signal is not limited, and the upper limit value is usually related to inherent properties of the circuit and the switch transistor Q1. In an example, the upper limit value of the frequency of the pulse signal may in a range of 100 kHz to 400 KHz.
In this example, the interrupt request and the pulse signal have a same frequency.
Generally, an "urgent event" needs to submit an application to the controller (send an electrical pulse signal) to request an "interrupt", namely, to request the controller to stop "a current task" first and process "an urgent task". The "application" process is referred to as an interrupt request. Specifically, in this example, when the controller receives the interrupt request, the controller is about to start the ADC, to obtain the electrical parameter sampled by the ADC.
In this example, the pulse signal may be generated through a timer integrated inside the controller. For example, a counter register TIMx_CNT (the counter is configured to count a clock signal), an auto-load register TIMx_ARR, a TIMx_CCRx register, a TIMx_CR1 register, and the like of a general-purpose timer TIMx are configured, and then a pulse-width modulation (PWM) signal is outputted through an output channel. A frequency of the PWM signal can be determined by the auto-load register TIMx_ARR, and a duty cycle of the PWM signal can be determined by the TIMx_CCRx register.
FIG. 3 and FIG. 5 are used as examples. In a specific implementation, the timer has a first channel CH1 and a second channel CH2. The first channel CH1 generates a pulse signal externally outputted for driving the first switch transistor Q1, and the second channel CH2 generates an interrupt request.
A counter register TIMx_CNT, an auto-load register TIMx_ARR, a TIMx_CCRx register, a TIMx_CR1 register, and the like of a general-purpose timer TIMx are configured. 1) A PWM edge-aligned mode uses an up-counting configuration, and an overflow value is a value of the auto-load register TIMx_ARR. 2) When a value of the counter register TIMx_CNT is less than a value of the TIMx_CCR1 register (a matching value), a high-level signal is generated. When the value of the counter register TIMx_CNT is greater than the value of the TIMx_CCR1 register (the matching value), a low-level signal is generated. Based on the above, a pulse signal generated by the first channel CH1 is as shown in the figure. 3) When the value of the counter register TIMx_CNT is less than a value of the TIMx_CCR2 register (a matching value), a low-level signal is generated. When the value of the counter register TIMx_CNT is greater than the value of the TIMx_CCR1 register (the matching value), a high-level signal is generated. Based on the above, the second channel CH1 generates an interrupt request, and a pulse signal corresponding to the interrupt request is as shown in the figure (the second channel CH1 may be mapped to an IO port of the controller and observed by an oscilloscope).
Based on the interrupt request generated by the second channel CH1, the interrupt request may be generated at a rising edge (as indicated by an arrow in the figure) or a falling edge of its corresponding pulse signal. In other words, when the value of the counter register TIMx_CNT matches the value of the TIMx_CCR2 register, the interrupt request is generated. In response to the interrupt request, the ADC can be started to obtain a voltage signal outputted by the operational amplifier U1. It should be noted that because the interrupt request is generated by a timer integrated inside the controller, the interrupt request is an internal interrupt request.
As can be seen from the figure, the frequency of the pulse signal is the same as the frequency of the pulse signal corresponding to the interrupt request.
Generally, a duty cycle of the pulse signal can be changed by adjusting the value of the TIMx_CCR1 register, while a duty cycle of the interrupt request generated by the second channel CH1 is fixed. In other words, the value of the TIMx_CCR2 register is fixed. The matching value for generating the interrupt request, that is, the value of the TIMx_CCR2 register, is often configured based on a parameter of the operational amplifier U1. For example, based on a slew rate parameter of the operational amplifier U1, a sampling time in a range of 1 µs to 4 µs may be configured. Specifically, for example, a sampling time of 1.5 µs, 2 µs, and 3 µs may be configured. The value of the TIMx_CCR2 register is configured based on the sampling time. The value of the TIMx_CCR1 register needs to be greater than the value of the TIMx_CCR2 register, so as to avoid unable to obtain the electrical parameter in the sampling circuit.
It should be noted that, corresponding to the example of FIG. 5, using a down-counting configuration is also feasible. Details are not described herein.
FIG. 3 and FIG. 6 are used as examples. In another specific implementation, the timer has a channel CH1. The channel CH1 generates a pulse signal externally outputted for driving the switch transistor Q1.
A counter register TIMx_CNT, an auto-load register TIMx_ARR, a TIMx_CCRx register, a TIMx_CR1 register, and the like of a general-purpose timer TIMx are configured. 1) In a PWM center-aligned mode, the counter is configured to count up first and then count down. 2) When a value of the counter register TIMx_CNT is less than a value of the TIMx_CCR1 register (a matching value), a low-level signal is generated. When the value of the counter register TIMx_CNT is greater than the value of the TIMx_CCR1 register, a high-level signal is generated.
Based on a pulse signal generated by a channel CH1, the controller is configured to generate an interrupt request at a moment (as shown at a point a in the figure) corresponding to a center point of the pulse signal generated by the channel CH1, where the moment corresponding to the center point of the pulse signal is a moment corresponding to an overflow value configured for generating the pulse signal. The overflow value is a value of the auto-load register TIMx_ARR. In other words, when the value of the counter register TIMx_CNT matches the value of the auto-load register TIMx_ARR, an interrupt request is generated. Based on the interrupt request, the ADC can be started to obtain a voltage signal outputted by the operational amplifier U1.
Generally, a continuous duration (as shown by t in the figure) corresponding to the overflow value and the matching value configured for generating the pulse signal, namely, the value of the auto-load register TIMx_ARR and the value of the TIMx_CCR1 register, is greater than a sampling time of the ADC.
As shown in the figure, a counting frequency of the counter is twice a frequency of the pulse signal. The frequency of the pulse signal is the same as the frequency of the pulse signal corresponding to the interrupt request.
FIG. 4 and FIG. 7 are used as examples. In yet another specific implementation, the timer has a first channel CH1 and a second channel CH2. The first channel CH1 generates a first pulse signal externally outputted for driving the first switch transistor Q1, and the second channel CH2 generates a second pulse signal externally outputted for driving the second switch transistor Q2.
A counter register TIMx_CNT, an auto-load register TIMx_ARR, a TIMx_CCRx register, a TIMx_CR1 register, and the like of a general-purpose timer TIMx are configured. 1) A PWM edge-aligned mode uses an up-counting configuration. 2) When a value of the counter register TIMx_CNT is less than a value of the TIMx_CCR1 register (a matching value), a high-level signal is generated. When the value of the counter register TIMx_CNT is greater than the value of the TIMx_CCR1 register (the matching value), a low-level signal is generated. Based on the above, a first pulse signal generated by the first channel CH1 is as shown in the figure. 3) A second pulse signal complementary to the first pulse signal is generated through the second channel CH2. In other words, when the value of the counter register TIMx_CNT is less than the value of the TIMx_CCR1 register, a low-level signal is generated. When the value of the counter register TIMx_CNT is greater than the value of the TIMx_CCR1 register (the matching value), a high-level signal is generated. 4) When generating the second pulse signal complementary to the first pulse signal through the second channel CH2, a matching interrupt is generated. In other words, when the value of the counter register TIMx_CNT matches the value of the TIMx_CCR1 register, an interrupt request is generated. Based on the interrupt request, the ADC can be started to obtain a voltage at a point a or a point b.
As shown in the figure, when the interrupt request is generated, the first switch transistor Q1 is turned off and the second switch transistor Q2 is turned on (assuming the first switch transistor Q1 and the second switch transistor Q2 are both turned on at a high level and turned off at a low level). The frequency of the pulse signal is the same as the frequency of the pulse signal corresponding to the interrupt request.
Generally, the timer may be configured, so that the second pulse signal generated by the second channel CH2 has a dead time, so as to prevent the first switch transistor Q1 and the second switch transistor Q2 from being turned on simultaneously.
In an example, the controller is configured to determine a resistance and/or a temperature of the heating element based on at least one of a voltage of the battery core, the electrical parameter of the sampling circuit, and a resistance of the sampling resistor.
Another implementation of this application further provides a control method of an aerosol generating device. Reference may be made to the above for the aerosol generating device.
The method includes:
externally outputting a pulse signal for driving the switch transistor, to control a heating operation of the heating element, and further configured to generate an interrupt request and respond to the interrupt request to obtain the electrical parameter sampled by the ADC.
It should be noted that, although the specification and the accompanying drawings of this application provide the preferred embodiments of this application, this application is not limited to the embodiments described in this specification. Further, a person of ordinary skill in the art may make improvements or modifications according to the above descriptions, and all of the improvements and modifications shall fall within the protection scope of the appended claims of this application.

Claims

An aerosol generating device, comprising:
a battery core, configured to provide electric power;

a heating element, electrically connected to the battery core to form a heating circuit, wherein the heating element is configured to heat an aerosol forming substrate to generate an aerosol, and a resistance value of the heating element is changeable with a change of a heating temperature;

a sampling resistor, electrically connected to the battery core and the heating element to form a sampling circuit;

a switch transistor, configured to turn on or turn off the heating circuit and/or the sampling circuit;

an analog-to-digital converter (ADC), configured to sample an electrical parameter of the sampling circuit; and

a controller, configured to externally output a pulse signal for driving the switch transistor, to control a heating operation of the heating element, and further configured to generate an interrupt request and respond to the interrupt request to obtain the electrical parameter sampled by the ADC.
The aerosol generating device according to claim 1, wherein a frequency of the pulse signal is above 10 kHz; preferably, the frequency of the pulse signal is above 12 kHz; further preferably, the frequency of the pulse signal is above 14 kHz; further preferably, the frequency of the pulse signal is above 16 kHz; and further preferably, the frequency of the pulse signal is above 20 kHz.
The aerosol generating device according to claim 1, wherein a frequency of the interrupt request is the same as the frequency of the pulse signal.
The aerosol generating device according to claim 1, wherein the switch transistor comprises a first switch transistor and a second switch transistor, the first switch transistor is configured to turn on or turn off the heating circuit, and the second switch transistor is configured to turn on or turn off the sampling circuit; and
the controller is configured to externally output a first pulse signal for driving the first switch transistor, and externally output a second pulse signal for driving the second switch transistor that is complementary to the first pulse signal; and further configured to generate the interrupt request when controlling the first switch transistor to be turned off and controlling the second switch transistor to be turned on.
The aerosol generating device according to claim 4, wherein the second pulse signal has a dead time.
The aerosol generating device according to claim 1, wherein the switch transistor is connected in series with the heating element and the sampling resistor; and the aerosol generating device further comprises an operational amplifier, one input terminal of the operational amplifier is electrically connected to one end of the sampling resistor, an other input terminal of the operational amplifier is electrically connected to an other end of the sampling resistor, and an output terminal of the operational amplifier is electrically connected to the ADC.
The aerosol generating device according to claim 6, wherein the controller is configured to generate the interrupt request at a moment corresponding to a center point of the pulse signal, wherein the moment corresponding to the center point of the pulse signal is a moment corresponding to an overflow value configured for generating the pulse signal.
The aerosol generating device according to claim 7, wherein a corresponding continuous duration between the overflow value configured for generating the pulse signal and a matching value is greater than a sampling time of the ADC.
The aerosol generating device according to claim 6, wherein the controller is configured to generate the pulse signal based on the configured overflow value and a first matching value, and generate the interrupt request based on the overflow value and a second matching value.
The aerosol generating device according to claim 9, wherein the first matching value is greater than the second matching value.
The aerosol generating device according to claim 9, wherein the second matching value is configured based on a parameter of the operational amplifier.
The aerosol generating device according to claim 1, wherein the controller is configured to determine a resistance and/or a temperature of the heating element based on at least one of a voltage of the battery core, the electrical parameter of the sampling circuit, and a resistance of the sampling resistor.
The aerosol generating device according to claim 1, wherein the ADC is integrated into the controller.
A control method for an aerosol generating device, wherein the aerosol generating device comprises:
a battery core, configured to provide electric power;

a heating element, electrically connected to the battery core to form a heating circuit, wherein the heating element is configured to heat an aerosol forming substrate to generate an aerosol, and a resistance value of the heating element is changeable with a change of a heating temperature;

a sampling resistor, electrically connected to the battery core and the heating element to form a sampling circuit;

a switch transistor, configured to turn on or turn off the heating circuit and/or the sampling circuit;

an ADC, configured to sample an electrical parameter of the sampling circuit; and

the control method comprises:
externally outputting a pulse signal for driving the switch transistor, to control a heating operation of the heating element, and further configured to generate an interrupt request and respond to the interrupt request to obtain the electrical parameter sampled by the ADC.