CN220255730U - Switching circuit and electronic atomization device - Google Patents

Abstract

The application discloses a switching circuit applied to an electronic atomization device and the electronic atomization device. The electronic atomizing device comprises a heating body for heating the aerosol-forming substrate to generate aerosol, and the switching circuit comprises a first switching tube, a controller and a voltage generation branch. The first switch tube is connected with the heating element and is used for controlling the power supply or the power failure of the heating element. The controller is used for outputting a control signal and a pulse width modulation signal. The voltage generation branch circuit is respectively connected with the controller and the first switching tube, and the voltage generation circuit is used for generating driving voltage to drive the first switching tube based on the pulse width modulation signal and the control signal. The driving voltage is used for enabling the absolute value of the pressure difference between the first end and the second end of the first switch tube to be larger than a preset threshold value. By the mode, the heating efficiency of the heating body can be improved.

Description

Switching circuit and electronic atomization device

Technical Field

The present disclosure relates to electronic atomization technology, and in particular, to a switching circuit and an electronic atomization device.

Background

In electronic nebulizing devices, aerosol-forming substrates, which may be liquid substrates such as tobacco tar, are typically heated by a heater to produce a smokable aerosol; but also solid substrates such as aerosol-generating articles, i.e. cigarettes.

The power supply and the power failure of the heating element are generally controlled through an NMOS tube or a PMOS tube. And the NMOS or PMOS tube is typically controlled by a controller in the electronic atomizing device.

However, the voltage output by the controller in the electronic atomization device is smaller, so that the on-resistance of the NMOS tube or the PMOS tube is larger, the power loss on the NMOS tube or the PMOS tube is higher, and the heating efficiency of the heating body is lower.

Disclosure of Invention

The application aims at providing a switching circuit and electron atomizing device, and this application can improve the heating efficiency of heat-generating body.

To achieve the above object, in a first aspect, the present application provides a switching circuit applied to an electronic atomizing device including a heating body that heats an aerosol-forming substrate to generate an aerosol, the switching circuit comprising:

the first switch tube is connected with the heating element and is used for controlling the power supply or the power failure of the heating element;

the controller is used for outputting a control signal and a pulse width modulation signal;

the voltage generation branch circuit is connected with the controller and the first switching tube respectively, and the voltage generation circuit is used for generating a driving voltage to drive the first switching tube based on the pulse width modulation signal and the control signal, wherein the driving voltage is used for enabling the absolute value of the pressure difference between the first end and the second end of the first switching tube to be larger than a preset threshold value.

In an optional manner, the first switching tube is an NMOS tube, and the voltage generating branch circuit includes a first capacitor;

the first capacitor is connected with the controller and the first switch tube respectively, is configured to be charged based on the voltage of the control signal when the pulse width modulation signal is at a low level, and is configured to boost the voltage of the control signal when the pulse width modulation signal is at a high level and then output a driving voltage.

In an alternative mode, a first end of the first capacitor is connected with the controller, and a second end of the first capacitor is connected with the controller and a first end of the first switch tube respectively; the first end of the first capacitor inputs a pulse width modulation signal, and the second end of the first capacitor inputs a control signal.

In an alternative manner, the voltage generating branch further includes a second capacitor, a first resistor, a first diode, and a second diode;

the anode of the first diode is connected with the second end of the first capacitor and the cathode of the second diode respectively, the anode of the second diode is connected with the first end of the second capacitor and the first end of the first resistor respectively, the second end of the first resistor is connected with the controller, the cathode of the first diode is connected with the second end of the second capacitor and the first end of the first switch tube respectively, the second end of the first switch tube is grounded, and the third end of the first switch tube is connected with the heating element.

In an alternative mode, the first switching tube is a PMOS functional, and the voltage generating branch includes a third capacitor and a switching sub-branch;

the third capacitor is respectively connected with the controller and the switch sub-branch, is configured to be charged when the pulse width modulation signal is at a high level, and is configured to generate negative pressure to the switch sub-branch when the pulse width modulation signal is at a low level;

the switch sub-branch is connected with the controller and the first switch tube respectively, and the switch sub-branch is configured to be conducted in response to the control signal so as to output a driving voltage based on negative pressure.

In an alternative mode, a first end of the third capacitor is connected with the controller, and a second end of the third capacitor is connected with the switch sub-branch; wherein the first end of the third capacitor inputs a pulse width modulation signal.

In an alternative manner, the voltage generating branch further comprises a fourth capacitor, a third diode and a fourth diode;

the first end of the fourth capacitor is respectively connected with the anode of the third diode and the switch subcircuit, the cathode of the third diode is respectively connected with the second end of the third capacitor and the anode of the fourth diode, and the cathode of the fourth diode and the second end of the fourth capacitor are grounded.

In an alternative manner, the switching sub-branch includes a second switching tube and a second resistor;

the first end of the second switch tube is connected with the controller and the first end of the second resistor respectively, the second end of the second resistor is grounded, the second end of the second switch tube is connected with the third capacitor, the third end of the second switch tube is connected with the first end of the first switch tube, the second end of the first switch tube is connected with the power supply, and the third end of the first switch tube is connected with the heating body; the first end of the second switching tube inputs a control signal.

In an alternative manner, the switching circuit further comprises a third switching tube;

the first end of the third switching tube is connected with the first end of the first switching tube, the second end of the third switching tube is connected with the first end of the first switching tube, and the third end of the third switching tube is connected with the third end of the first switching tube;

and the first switching tube and the third switching tube are the same type.

In a second aspect, the present application provides an electronic atomizing device comprising:

a heating element for heating the aerosol-forming substrate to generate an aerosol;

the power supply is used for supplying power to the heating body;

and the switch circuit is connected with the heating element and is used for controlling the power on and power off of the heating element.

The beneficial effects of this application are: the switching circuit applied to the electronic atomization device comprises a first switching tube, a controller and a voltage generation branch circuit. The first switch tube is used for controlling the power supply or the power failure of the heating element. The controller is used for outputting a control signal and a pulse width modulation signal. The voltage generating circuit is used for generating a driving voltage to drive the first switching tube based on the pulse width modulation signal and the control signal. The driving voltage is used for enabling the absolute value of the pressure difference between the first end and the second end of the first switch tube to be larger than a preset threshold value. Therefore, the absolute value of the pressure difference between the first end and the second end of the first switching tube is kept larger, so that the conduction resistance of the first switching tube is reduced, namely, the power damage on the first switching tube is reduced, and the heating efficiency of the heating body is improved.

Drawings

One or more embodiments are illustrated by way of example and not limitation in the figures of the accompanying drawings, in which like references indicate similar elements, and in which the figures of the drawings are not to be taken in a limiting sense, unless otherwise indicated.

Fig. 1 is a schematic structural diagram of an electronic atomization device according to an embodiment of the present disclosure;

fig. 2 is a schematic diagram of a circuit structure in an electronic atomization device according to an embodiment of the present disclosure;

fig. 3 is a schematic diagram of a circuit structure in an electronic atomization device according to a second embodiment of the present disclosure;

fig. 4 is a schematic diagram of a circuit structure in an electronic atomization device according to a third embodiment of the present application;

fig. 5 is a schematic diagram of a circuit structure in an electronic atomization device according to a fourth embodiment of the present application;

fig. 6 is a schematic diagram of a circuit structure in an electronic atomization device according to a fifth embodiment of the present application.

Detailed Description

For the purposes of making the objects, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions of 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 apparent that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments herein without making any inventive effort, are intended to be within the scope of the present application.

An electronic atomising device refers to any device which, in use, heats an aerosol-forming substrate to generate an aerosol. In particular, an apparatus is known which heats an aerosol-forming substrate to form an inhalable aerosol without burning or igniting the aerosol-generating article. Such devices are sometimes described as "heating non-combustion" devices or "tobacco heating products" or "tobacco heating devices" or the like.

Similarly, there are also so-called e-cigarette devices, which typically evaporate an aerosol-forming substrate in liquid form, which may or may not contain nicotine. In other embodiments, the electronic atomizing device provides the aerosol or vapor by heating an aerosol-forming substrate in solid form. In a particular embodiment, the electronic atomizing device is a tobacco heating product.

Referring to fig. 1, fig. 1 is a schematic structural diagram of an electronic atomization device according to an embodiment of the present application. As shown in fig. 1, the electronic atomizing device 1000 includes a heating element 200 and a power supply 300.

Wherein the heat-generating body 200 is used to heat an aerosol-forming substrate in the aerosol-generating article 500 to generate an aerosol, the aerosol-generating article 500 is at least partially removably received within the heating chamber 400 such that the aerosol-forming substrate in the aerosol-generating article 500 may be heated in the heating chamber 400. For example, the heating body 200 is disposed close to the heating chamber 400 such that heat from the heating body 200 heats the aerosol-forming substrate to volatilize the aerosol without burning the aerosol-forming substrate.

The heating element 200 has a substantially tubular structure, and an inner hollow portion of the tubular structure constitutes at least part of the heating chamber 400. In other embodiments, other shapes and configurations of the heat-generating body 200 and the heating chamber 400 may be selectively used, such as the heat-generating body 200 being configured to be insertable into the aerosol-generating article 500 for heating.

The heat-generating body 200 may be a resistive heat-generating body, meaning that when power is applied to the heat-generating body 200, the resistance in the heat-generating body 200 converts electrical energy into thermal energy, which can heat the aerosol-generating article 500. The heating body 200 may be in the form of a resistive wire, a mesh, a coil, and/or a plurality of wires. In some embodiments, the heating body 200 may be a thin film heater, such as a resistive thin film heater or an infrared thin film heater.

The heating element 200 may also be a conductor or a semiconductor, which may include a metal or a metal alloy. Metals are excellent conductors of electrical and thermal energy. Suitable metals include, but are not limited to: copper, aluminum, platinum, tungsten, gold, silver, and titanium. Suitable metal alloys include, but are not limited to: nichrome and stainless steel.

The heat-generating body 200 may also be an electromagnet through which a varying current flows to generate a varying magnetic field that causes one or more eddy currents to be generated inside the heat-generating body 200 so that the heat-generating body 200 is heated.

The power supply 300 is electrically connected to the heating element 200 for supplying power to the heating element 200, which may be a power supply that supplies power to the heating element 200, such as a lithium ion battery, a nickel battery, an alkaline battery, and/or other batteries, etc., and the power supply 300 may supply electric power to the heating element 200 when necessary.

Similar to fig. 1, there is also a so-called e-cigarette device, which typically evaporates an aerosol-forming substrate in liquid form, which may or may not contain nicotine. The specific structure is not limited herein, and reference is made to the prior art.

Referring to fig. 2, fig. 2 is a schematic circuit diagram of an electronic atomization device according to an embodiment of the present application. Wherein the electronic atomizing device 1000 is configured to heat an aerosol-forming substrate to generate an aerosol. In some embodiments, the specific implementation of the electronic atomization device 1000 may refer to the description of fig. 1, and will not be repeated here.

As shown in fig. 2, the electronic atomizing device 1000 further includes a switching circuit 100.

The switching circuit 100 includes a first switching tube Q1, a controller 10, and a voltage generation branch 20. The first switching tube Q1 is connected to the heating element 200. The voltage generation branch 20 is connected to the controller 10 and the first switching transistor Q1.

In some embodiments, the controller 10 may be a general purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), a single-chip, ARM (Acorn RISC Machine) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof. Also, the controller 10 may be any conventional processor, controller, microcontroller, or state machine. The controller 10 may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP and/or any other such configuration.

Specifically, the first switching tube Q1 is used to control the power on or off of the heating element 200. The controller 10 is used for outputting control signals and pulse width modulation signals. The voltage generation branch 20 is connected to the controller 10 and the first switching transistor Q1, and the voltage generation circuit 60 is configured to generate a driving voltage to drive the first switching transistor Q1 based on the pulse width modulation signal and the control signal.

The driving voltage is used for enabling the absolute value of the pressure difference between the first end and the second end of the first switch tube Q1 to be larger than a preset threshold value. The preset threshold may be set according to an actual application, which is not limited in this embodiment, for example, in some embodiments, the preset threshold may be set according to a pressure difference between the first end and the second end of the first switching tube Q1 when the first switching tube Q1 is turned on stably. For example, in an embodiment, the first switching tube Q1 is a MOS tube, and when the absolute value of the voltage difference between the first end and the second end of the first switching tube Q1 is greater than 4.5V, the first switching tube Q1 can be stably turned on, and the on-resistance is smaller, the preset threshold may be set to be greater than or equal to 4.5V.

In the related art, due to the fact that the voltage output by the controller in the electronic atomization device is smaller, the on-resistance of the NMOS tube or the PMOS tube controlled by the controller is larger, the power loss on the NMOS tube or the PMOS tube is higher, and therefore the heating efficiency of the heating body is lower.

In the embodiment of the present application, the driving voltage obtained by reasonably setting the preset threshold value drives the first switching tube Q1, so that the absolute value of the pressure difference between the first end and the second end of the first switching tube Q1 can be kept large. Accordingly, the on-resistance of the first switching tube Q1 can be reduced, which is advantageous in reducing the power damage on the first switching tube Q1, and thus the heating efficiency of the heating body 200 can be improved.

Referring to fig. 3, a circuit structure corresponding to fig. 2 is exemplarily shown in fig. 3.

In one embodiment, the first switching tube Q1 is an NMOS tube. The gate G of the NMOS tube is a first end of the first switching tube Q1, the source S of the NMOS tube is a second end of the first switching tube Q1, and the drain D of the NMOS tube is a third end of the first switching tube Q1.

The voltage generating branch 20 comprises a first capacitance C1. The first capacitor C1 is connected to the controller 10 and the first switching transistor Q1, respectively. Specifically, a first end of the first capacitor C1 is connected to the controller 10, and a second end of the first capacitor C1 is connected to the controller 10 and a first end of the first switching tube Q1, respectively. The first end of the first capacitor C1 inputs a pulse width modulation signal, and the second end of the first capacitor C1 inputs a control signal.

The first capacitor C1 is configured to be charged based on the voltage of the control signal when the pulse width modulation signal is at a low level, and configured to boost the voltage of the control signal when the pulse width modulation signal is at a high level and then output the driving voltage to the first switching transistor Q1.

In this embodiment, the NMOS transistor is driven on by a positive voltage. The voltage of the control signal is boosted and then acts on the first switching tube Q1, so that on one hand, the first switching tube Q1 can be driven to be conducted; on the other hand, a larger voltage can be provided to act on the gate of the first switching transistor Q1, so that the gate-source voltage (the voltage difference between the gate G and the source S) of the first switching transistor Q1 is larger, the on-voltage drop of the first switching transistor Q1 is smaller, and the power loss of the first switching transistor Q1 is lower.

In an embodiment, the voltage generating branch 100 further includes a second capacitor C2, a first resistor R1, a first diode D1, and a second diode D2.

The anode of the first diode D1 is connected to the second end of the first capacitor C1 and the cathode of the second diode D2, the anode of the second diode D2 is connected to the first end of the second capacitor C2 and the first end of the first resistor R1, the second end of the first resistor R1 is connected to the controller 10, the cathode of the first diode D1 is connected to the second end of the second capacitor C2 and the first end of the first switching tube Q1, the second end of the first switching tube Q1 is grounded GND, and the third end of the first switching tube Q1 is connected to the heating element 200.

Specifically, the first resistor R1 is a current limiting resistor. The second capacitor C2 is used for filtering. The first diode D1 and the second diode D2 function to prevent the reverse flow of voltage and current from the cathode to the anode of the diode by using the single-turn-on characteristic of the diode, so as to protect the controller 10.

In one embodiment, the voltage generating branch 100 further includes a third resistor R3.

The first end of the third resistor R3 is connected to the first end of the first switching tube Q1, and the second end of the third resistor R3 is grounded GND.

Specifically, the third resistor R3 is used to reduce interference noise and common mode noise caused by high-speed switching by limiting the transient current input to the gate of the first switching tube Q1, thereby reducing interference effects on other electronic components and risk of circuit damage. In addition, the third resistor R3 may also increase the switching speed of the first switching transistor Q1.

The principle of the circuit configuration shown in fig. 3 is explained below. The first end of the first capacitor C1 is input with a pulse width modulation signal. A pulse width modulated (Pulse Width Modulation, PWM) signal is a periodic signal that is characterized by a pulse width that can vary over time while the period of the pulse remains unchanged. By varying the duty cycle of the pulses (the ratio of the width of the high level pulses to the whole period) an accurate control of the output signal can be achieved.

The second terminal of the first resistor R1 is input with a control signal. The embodiment will be described by taking the example in which the voltage of the control signal outputted from the controller 10 is 3V, the voltage corresponding to the high level of the pulse width modulation signal is 3V, and the voltage corresponding to the low level is 0V. Meanwhile, assuming that the gate-source voltage of the first switching tube Q1 is greater than 4.5V, the first switching tube Q1 can be stably turned on, and the on-resistance is small.

During the period that the pulse width modulation signal is at the low level, the voltage of the control signal charges the first capacitor C1 through the first resistor R1 and the second diode D2. And charges the first capacitor C1 to a voltage of 3V across it.

The pwm signal is switched to a high level, and the first terminal voltage of the first capacitor C1 is 3V during the period in which the pwm signal is at the high level. In this case, since the voltage difference across the first capacitor C1 cannot be abrupt, the second end of the first capacitor C1 is pulled up from 3V to 6V. The voltage of 6V decreases to 5.7V after passing through the first diode D1 (for example, the voltage drop of the first diode D1 is 0.3V), that is, the gate voltage of the first switching tube Q1 is 5.7V. The source of the first switch Q1 is grounded GND, and the source voltage of the first switch Q1 is 0V. In summary, the gate-source voltage of the first switching tube Q1 is 5.7V > 4.5V, so the first switching tube Q1 can be stably turned on, and the on-resistance is reduced. Thus, the power damage on the first switching tube Q1 is small, and the heating efficiency of the heating body is high.

In addition, when the first switching tube Q1 needs to be controlled to be turned off, the controller 10 stops outputting the control signal and outputs 0V at the same pin, so that the gate of the first switching tube Q1 is grounded GND after passing through the second capacitor C2 and the first resistor R1. Then, the controller 10 stops outputting the pwm signal and outputs 0V at the same pin to act on the gate of the first switch Q1 through the first capacitor C1 and the first diode D1. Further, the gate-source voltage of the first switching transistor Q1 is 0, and the first switching transistor Q1 is turned off.

In another embodiment, as shown in fig. 4, a switching tube connected in parallel to the first switching tube Q1 may be further added to further reduce the on-resistance of the first switching tube Q1, which may cause power loss when the first switching tube Q1 is turned on. The specific implementation process is as follows.

The switching circuit 100 further includes a third switching transistor Q3. The first end of the third switching tube Q3 is connected to the first end of the first switching tube Q1, the second end of the third switching tube Q3 is connected to the first end of the first switching tube Q1, and the third end of the third switching tube Q3 is connected to the third end of the first switching tube Q1.

And, the first switching transistor Q1 is the same type as the third switching transistor Q3. That is, when the first switching transistor Q1 is an NMOS transistor, the third switching transistor Q3 is also an NMOS transistor.

Specifically, when the first switching tube Q1 and the third switching tube Q3 are both turned on, the on-resistance of the first switching tube Q1 and the on-resistance of the third switching tube Q3 are connected in parallel, and the total resistance after the parallel connection is smaller than the on-resistance of the first switching tube Q1, so as to achieve the purpose of reducing power loss.

It should be noted that, in this embodiment, two switching tubes (including the first switching tube Q1 and the third switching tube Q3) connected in parallel are taken as an example, and in other embodiments, three or more switching tubes connected in parallel may be used, which is not particularly limited in this embodiment of the present application.

Referring to fig. 5, another circuit structure corresponding to fig. 2 is exemplarily shown in fig. 5.

In one embodiment, as shown in fig. 5, the first switching tube Q1 is a PMOS transistor, and the voltage generating branch 20 includes a third capacitor C3 and a switching sub-branch 21.

The third capacitor C3 is connected to the controller 10 and the switch sub-branch 21, respectively. The switching sub-branch 21 is connected to the controller 10 and the first switching tube Q1, respectively. Specifically, a first end of the third capacitor C3 is connected to the controller 10, and a second end of the third capacitor C3 is connected to the switch sub-branch 21. Wherein, the first end of the third capacitor C3 inputs the pulse width modulation signal.

In this embodiment _， The third capacitor C3 is configured to charge when the pulse width modulated signal is at a high level and is configured to generate a negative voltage to the switching sub-branch 21 when the pulse width modulated signal is at a low level. The switching sub-branch 21 is configured to be turned on in response to a control signal to output a driving voltage based on the negative pressure.

The PMOS tube is driven to be conducted by negative voltage. By applying the output negative voltage to the first switching tube Q1, on the one hand, the first switching tube Q1 can be driven to be turned on; on the other hand, the absolute value of the gate-source voltage of the first switching tube Q1 can be increased to reduce the on-voltage drop of the first switching tube Q1, thereby reducing the power loss of the first switching tube Q1.

In an embodiment, the voltage generating branch 20 further includes a fourth capacitor C4, a third diode D3, and a fourth diode D4.

The first end of the fourth capacitor C4 is connected to the anode of the third diode D3 and the switch sub-branch 21, the cathode of the third diode D3 is connected to the second end of the third capacitor C3 and the anode of the fourth diode D4, and the cathode of the fourth diode D4 and the second end of the fourth capacitor C4 are grounded GND.

Specifically, the fourth capacitor C4 is used for filtering. The third diode D3 and the fourth diode D4 function to prevent the reverse flow of voltage and current from the cathode to the anode of the diode by using the single-turn-on characteristic of the diode, so as to protect the controller 10.

In one embodiment, the switch sub-branch 21 includes a second switch Q2 and a second resistor R2.

The first terminal G of the second switching tube Q2 is connected to the controller 10 and the first terminal of the second resistor R2, the second terminal S of the second resistor R2 is grounded GND, the second terminal S of the second switching tube Q2 is connected to the third capacitor C3, and the third terminal D of the second switching tube Q2 is connected to the first terminal G of the first switching tube Q1. The first terminal G of the second switching tube Q2 inputs a control signal.

Specifically, when the controller 10 outputs a control signal to the first terminal of the second switching tube Q2, the second switching tube Q2 is turned on.

In one embodiment, the voltage generation branch 100 further includes a fourth resistor R4.

The first end of the fourth resistor R4 is connected to the first end of the first switching tube Q1, and the second end of the fourth resistor R4 is connected to the second end of the first switching tube Q1 and the power supply 300, respectively.

Specifically, the fourth resistor R4 is used to reduce interference noise and common mode noise caused by high-speed switching by limiting the transient current input to the gate of the first switching tube Q1, thereby reducing interference effects on other electronic components and risk of circuit damage. In addition, the fourth resistor R4 may also increase the switching speed of the first switching transistor Q1.

The principle of the circuit configuration shown in fig. 5 is explained below. The first end of the third capacitor C3 is input with a pulse width modulation signal. The first terminal of the second switching transistor Q2 receives a control signal. The embodiment will be described by taking the example in which the voltage of the control signal outputted from the controller 10 is 3V, the voltage corresponding to the high level of the pulse width modulation signal is 3V, and the voltage corresponding to the low level is 0V. Meanwhile, assuming that the absolute value of the gate-source voltage of the first switching tube Q1 is greater than 4.5V, the first switching tube Q1 can be stably turned on, and the on-resistance is small.

During the period when the pulse width modulation signal is at the high level, 3V in the pulse width modulation signal forms a loop with the third capacitor C3 and the second diode D4, and the third capacitor C3 is charged. The third capacitor C3 is charged to a voltage of 3V across it.

Thereafter, the pulse width modulation signal is switched to a low level. The first terminal voltage of the third capacitor C3 is 0V during the low level of the pulse width modulated signal. In this case, the second end of the third capacitor C3 is pulled down from 0V to-3V, since the voltage difference across the third capacitor C3 cannot be abrupt. 3V rises to-2.7V after passing through the third diode D3 (for example, the voltage drop of the third diode D3 is 0.3V), i.e., the voltage on the source of the second switching tube Q2 is-2.7V.

Next, the controller 10 outputs a control signal to the gate of the second switching tube Q2 to drive the second switching tube Q2 to be turned on. 2.7V acts on the gate of the first switching tube Q1 via the second switching tube Q2. The source of the first switching tube Q1 is connected to the power supply 300, and the source voltage of the first switching tube Q1 is the voltage output by the power supply 300. In summary, the gate-source voltage of the first switching transistor Q1 is the difference between-2.7V and the voltage output by the power supply 300. By configuring the voltage output by the power supply to exceed 1.8V, the gate-source voltage of the first switching tube Q1 can be made to be greater than 4.5V, and the first switching tube Q1 can be turned on stably with reduced on-resistance. Thus, the power damage on the first switching tube Q1 is small, and the heating efficiency of the heating body is high.

In addition, when the first switching tube Q1 needs to be controlled to be turned off, the controller 10 stops outputting the pulse width modulation signal and outputs 0V at the same pin, and at this time, no negative pressure is generated. Then, the controller 10 stops outputting the control signal and outputs 0V at the same pin to turn off the second switching tube Q2. Then, the first switching tube Q1 is also turned off.

In another embodiment, as shown in fig. 6, a switching tube connected in parallel to the first switching tube Q1 may be added on the basis of the circuit structure shown in fig. 5, so as to further reduce the on-resistance of the first switching tube Q1, which may cause power loss when the first switching tube Q1 is turned on. The specific implementation process is as follows.

The switching circuit 100 further includes a third switching transistor Q3. The first end of the third switching tube Q3 is connected to the first end of the first switching tube Q1, the second end of the third switching tube Q3 is connected to the first end of the first switching tube Q1, and the third end of the third switching tube Q3 is connected to the third end of the first switching tube Q1.

And, the first switching transistor Q1 is the same type as the third switching transistor Q3. That is, when the first switching tube Q1 is a PMOS tube, the third switching tube Q3 is also a PMOS tube.

Specifically, when the first switching tube Q1 and the third switching tube Q3 are both turned on, the on-resistance of the first switching tube Q1 and the on-resistance of the third switching tube Q3 are connected in parallel, and the total resistance after the parallel connection is smaller than the on-resistance of the first switching tube Q1, so as to achieve the purpose of reducing power loss.

It should be noted that, in this embodiment, two switching tubes (including the first switching tube Q1 and the third switching tube Q3) connected in parallel are taken as an example, and in other embodiments, three or more switching tubes connected in parallel may be used, which is not particularly limited in this embodiment of the present application.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present application, and are not limiting thereof; the technical features of the above embodiments or in the different embodiments may also be combined under the idea of the present application, the steps may be implemented in any order, and there are many other variations of the different aspects of the present application as described above, which are not provided in details for the sake of brevity; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims (10)

1. A switching circuit for use in an electronic atomizing device including a heat generating body that heats an aerosol-forming substrate to generate an aerosol, the switching circuit comprising:

the first switch tube is connected with the heating body and is used for controlling the power supply or the power failure of the heating body;

the controller is used for outputting a control signal and a pulse width modulation signal;

the voltage generation branch circuit is respectively connected with the controller and the first switching tube, and the voltage generation circuit is used for generating a driving voltage to drive the first switching tube based on the pulse width modulation signal and the control signal, wherein the driving voltage is used for enabling the absolute value of the pressure difference between the first end and the second end of the first switching tube to be larger than a preset threshold value.

2. The switching circuit of claim 1, wherein the first switching tube is an NMOS tube and the voltage generating branch comprises a first capacitor;

the first capacitor is respectively connected with the controller and the first switch tube, is configured to be charged based on the voltage of the control signal when the pulse width modulation signal is at a low level, and is configured to boost the voltage of the control signal when the pulse width modulation signal is at a high level and then output the driving voltage.

3. The switching circuit of claim 2, wherein a first end of the first capacitor is connected to the controller and a second end of the first capacitor is connected to the controller and the first end of the first switching tube, respectively;

the first end of the first capacitor inputs the pulse width modulation signal, and the second end of the first capacitor inputs the control signal.

4. The switching circuit of claim 2, wherein the voltage generation branch further comprises a second capacitor, a first resistor, a first diode, and a second diode;

the anode of the first diode is connected with the second end of the first capacitor and the cathode of the second diode respectively, the anode of the second diode is connected with the first end of the second capacitor and the first end of the first resistor respectively, the second end of the first resistor is connected with the controller, the cathode of the first diode is connected with the second end of the second capacitor and the first end of the first switch tube respectively, the second end of the first switch tube is grounded, and the third end of the first switch tube is connected with the heating element.

5. The switching circuit of claim 1 wherein the first switching tube is a PMOS transistor and the voltage generating branch comprises a third capacitor and a switching sub-branch;

the third capacitor is respectively connected with the controller and the switch sub-branch, is configured to be charged when the pulse width modulation signal is at a high level, and is configured to generate negative pressure to the switch sub-branch when the pulse width modulation signal is at a low level;

the switching sub-branch is connected with the controller and the first switching tube respectively, and the switching sub-branch is configured to be turned on in response to the control signal so as to output the driving voltage based on the negative pressure.

6. The switching circuit of claim 5, wherein a first end of the third capacitor is connected to the controller and a second end of the third capacitor is connected to the switching sub-branch;

wherein the first end of the third capacitor inputs the pulse width modulation signal.

7. The switching circuit of claim 6 wherein the voltage generation branch further comprises a fourth capacitor, a third diode, and a fourth diode;

the first end of the fourth capacitor is connected with the anode of the third diode and the switch subcircuit respectively, the cathode of the third diode is connected with the second end of the third capacitor and the anode of the fourth diode respectively, and the cathode of the fourth diode and the second end of the fourth capacitor are grounded.

8. The switching circuit of claim 5, wherein the switching subcircuit includes a second switching tube and a second resistor;

the first end of the second switching tube is connected with the controller and the first end of the second resistor respectively, the second end of the second resistor is grounded, the second end of the second switching tube is connected with the third capacitor, the third end of the second switching tube is connected with the first end of the first switching tube, the second end of the first switching tube is connected with a power supply, and the third end of the first switching tube is connected with the heating element;

the first end of the second switching tube inputs the control signal.

9. The switching circuit according to any one of claims 1 to 8, further comprising a third switching tube;

the first end of the third switching tube is connected with the first end of the first switching tube, the second end of the third switching tube is connected with the first end of the first switching tube, and the third end of the third switching tube is connected with the third end of the first switching tube;

and the first switching tube and the third switching tube are the same in type.

10. An electronic atomizing device, comprising:

a heating element for heating the aerosol-forming substrate to generate an aerosol;

the power supply is used for supplying power to the heating element;

and a switch circuit according to any one of claims 1 to 9, wherein the switch circuit is connected to the heating element, and the switch circuit is used for controlling power supply and power failure of the heating element.