A control circuit of an electronic atomizer and an electronic atomizer

Abstract

The present invention discloses a control circuit and an electronic atomizer for an electronic atomizer. The control circuit is integrated on a control chip including a pin CELL, a pin Vout, and a pin Gnd. The control circuit includes a control logic module, a power supply module, a clamping element, a resistor, and an NMOS power transistor. A first end of the control logic module is connected to a first end of the power supply module. The resistor is connected in series between a second end of the power supply module and the pin CELL. A second end of the control logic module and a first end of the clamping element are commonly connected to the gate of the NMOS power transistor. The drain of the NMOS power transistor is connected to the pin CELL, and the source of the NMOS power transistor is connected to the pin Vout. A third end of the control logic module and a second end of the clamping element are commonly connected to the pin Gnd. Two ends of a heating wire are respectively connected to the pin Vout and the pin Gnd. A battery of the electronic atomizer is connected between the pin CELL and the pin Gnd. When the battery of the electronic atomizer is reversely connected, current is allowed to flow through the NMOS power transistor, avoiding out-of-control current from damaging the control chip and improving the safety of the electronic atomizer.

Description

Technical Field

[0001] This application relates to the technical field of electronic atomizers, and more specifically, to a control circuit and an electronic atomizer for an electronic atomizer. Background Art

[0002] An electronic atomizer is an electronic product that imitates cigarettes. It atomizes e-liquid through a heating wire to generate smoke for inhalation, and can meet the needs of smokers for e-liquids with different concentrations and various flavors. Therefore, it is widely loved by smokers, and there are already a large number of mainstream products on the market.

[0003] In practical applications, the positive and negative electrodes of the battery in an electronic atomizer product are often connected reversely. Once the positive and negative electrodes of the battery are connected reversely, the control chip is equivalent to a diode to short-circuit the battery, and the control chip inside cannot control the current flowing through it, which is easy to cause the control chip to be directly "burned" out, and may also cause "explosion of the device" due to excessive current, resulting in serious safety hazards.

[0004] Therefore, how to provide a control circuit that can improve the safety of an electronic atomizer is a technical problem to be solved at present. Summary of the Invention

[0005] The present invention discloses a control circuit for an electronic atomizer to solve the technical problem of low safety of the electronic atomizer caused by reverse connection of the battery in the prior art.

[0006] The control circuit is integrated on a control chip including a pin CELL, a pin Vout, and a pin Gnd. The control circuit includes a control logic module, a power supply module, a clamping element, a resistor, and an NMOS power transistor. Among them,

[0007] The control logic module is used to generate a control signal for the electronic atomizer according to a preset control logic. The power supply module is used to supply power to the control logic module. The first end of the control logic module is connected to the first end of the power supply module. The resistor is connected in series between the second end of the power supply module and the pin CELL. The second end of the control logic module and the first end of the clamping element are commonly connected to the gate of the NMOS power transistor. The drain of the NMOS power transistor is connected to the pin CELL. The source of the NMOS power transistor is connected to the pin Vout. The third end of the control logic module and the second end of the clamping element are commonly connected to the pin Gnd. The two ends of the heating wire of the electronic atomizer are respectively connected to the pin Vout and the pin Gnd. The battery of the electronic atomizer is connected between the pin CELL and the pin Gnd;

[0008] Wherein, when the positive electrode of the battery is connected to the pin Gnd and the negative electrode of the battery is connected to the pin CELL, the clamping element clamps a PN junction voltage drop between the gate of the NMOS power transistor and the pin Gnd.

[0009] In some embodiments of the present application, the control chip further includes a pin SENSOR, the pin SENSOR is connected to the fourth end of the control logic module, the control circuit further includes a first ESD device, a second ESD device, a first protection element and a second protection element, a first end of the first protection element is connected to a second end of the power supply module, the first ESD device is connected in series between a second end of the first protection element and a first end of the second protection element, the second ESD device is connected in series between a second end of the second protection element and a third end of the control logic module, and a first end of the first ESD device and the second protection element is connected to the pin SENSOR;

[0010] Wherein, the pin SENSOR is used to enable the control logic module to detect whether there is a smoke inhalation action, the first protection element is used to prevent current from flowing back into the first ESD device, and the second protection element is used to prevent current from flowing back into the second ESD device.

[0011] In some embodiments of the present application, the structures of the first ESD device and the second ESD device include a diode structure, or a ggnmos structure, or a PNP structure.

[0012] In some embodiments of the present application, the control chip further includes:

[0013] A pin USB, connected to the control logic module, for enabling the control logic module to perform charge management on the battery;

[0014] A pin LED, connected to the control logic module, for enabling the control logic module to control the LED of the electronic atomizer.

[0015] In some embodiments of the present application, the impedance of the heating wire is less than the impedance of the resistor.

[0016] Correspondingly, the present invention further provides an electronic atomizer, including the control circuit as described above.

[0017] By applying the above technical solution, the control circuit is integrated on a control chip including pin CELL, pin Vout, and pin Gnd. The control circuit includes a control logic module, a power supply module, a clamping element, a resistor, and an NMOS power transistor. Among them, the control logic module is used to generate a control signal for the electronic atomizer according to a preset control logic. The power supply module is used to supply power to the control logic module. The first end of the control logic module is connected to the first end of the power supply module. The resistor is connected in series between the second end of the power supply module and pin CELL. The second end of the control logic module and the first end of the clamping element are commonly connected to the gate of the NMOS power transistor. The drain of the NMOS power transistor is connected to pin CELL, and the source of the NMOS power transistor is connected to pin Vout. The third end of the control logic module and the second end of the clamping element are commonly connected to pin Gnd. Both ends of the heating wire are respectively connected to pin Vout and pin Gnd. A battery of the electronic atomizer is connected between pin CELL and pin Gnd. When the battery of the electronic atomizer is reversely connected, the current flows through the NMOS power transistor, avoiding current out-of-control damage to the control chip and improving the safety of the electronic atomizer. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those skilled in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0019] Figure 1 FIG. shows a schematic structural diagram of a control circuit of an electronic atomizer proposed in an embodiment of the present invention;

[0020] Figure 2 FIG. shows a schematic diagram of the current path when the battery is reversely connected and the NMOS power transistor is not turned on in an embodiment of the present invention;

[0021] Figure 3 FIG. shows a schematic diagram of the current path when the battery is reversely connected and the NMOS power transistor is turned on in an embodiment of the present invention;

[0022] Figure 4 FIG. shows a schematic structural diagram of a control circuit of an electronic atomizer proposed in another embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, rather than all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0024] The terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of this application, unless otherwise specified, the meaning of "a plurality" is two or more.

[0025] An embodiment of this application provides a control circuit for an electronic atomizer. As Figure 1 shown, the control circuit is integrated on a control chip including pin CELL, pin Vout, and pin Gnd. The control circuit includes a control logic module, a power supply module power, a clamping element Vz, a resistor R1, and an NMOS power transistor (i.e., an N-type power transistor) M1. Among them,

[0026] The control logic module is used to generate a control signal for the electronic atomizer according to a preset control logic. The power supply module power is used to supply power to the control logic module. The first end of the control logic module is connected to the first end of the power supply module power. The resistor R1 is connected in series between the second end of the power supply module power and pin CELL. The second end of the control logic module and the first end of the clamping element Vz are commonly connected to the gate of the NMOS power transistor M1. The drain of the NMOS power transistor M1 is connected to pin CELL, the source of the NMOS power transistor M1 is connected to pin Vout, the third end of the control logic module and the second end of the clamping element Vz are commonly connected to pin Gnd. The two ends of the heating wire of the electronic atomizer are respectively connected to pin Vout and pin Gnd. A battery of the electronic atomizer is connected between pin CELL and pin Gnd.

[0027] In this embodiment, when the battery is connected correctly, that is, when the positive pole of the battery is connected to pin CELL and the negative pole of the battery is connected to pin Gnd, the clamping element Vz is cut off; when the battery is connected reversely, that is, when the positive pole of the battery is connected to pin Gnd and the negative pole of the battery is connected to pin CELL, all the devices inside the control chip are equivalently generated into diodes. As Figure 2 shown in "Path 1" in, the current flows through the equivalent parasitic diode V0 of the control chip, the resistor R1, and pin CELL in sequence to conduct.

[0028] When the battery is connected reversely, the battery voltage drop includes the voltage drop V PN on the equivalent parasitic diode V0 and the voltage drop on the resistor R1. The voltage drop on the resistor R1 is Vdd - V PN . The clamping element Vz clamps a PN junction voltage drop between the gate of the NMOS power transistor M1 and pin Gnd. When the reverse current makes the voltage drop I * R1 on the resistor R1 greater than the threshold voltage Vth of the NMOS power transistor M1, the NMOS power transistor M1 will turn on and conduct. As Figure 3As shown in "Path 2" in , most of the current of the battery conducts along the pin Gnd - heating wire - NMOS power transistor M1 - pin CELL. At this time, the internal logic circuit of the control chip will not be damaged. At the same time, since the size of the NMOS power transistor M1 itself is large enough, the NMOS power transistor M1 will not burn out. Coupled with the self-impedance of the heating wire and the NMOS power transistor M1, the current will not get out of control, so the control chip will not burn out.

[0029] Optionally, as Figure 1 shown, the clamping element Vz is a zener diode. The first end of the clamping element Vz is the cathode of the zener diode, and the second end of the clamping element Vz is the anode of the zener diode. Those skilled in the art can select other types of clamping elements according to actual needs, which does not affect the protection scope of this application.

[0030] Optionally, the above PN junction voltage drop is about 0.6V.

[0031] To further improve the safety of the electronic atomizer, in some embodiments of this application, as Figure 4 shown, the control chip further includes a pin SENSOR. The pin SENSOR is connected to the fourth end of the control logic module. The control circuit further includes a first ESD (Electro-Static discharge) device ESD1, a second ESD device ESD2, a first protection element V1, and a second protection element V2. The first end of the first protection element V1 is connected to the second end of the power supply module power. The first ESD device ESD1 is connected in series between the second end of the first protection element V1 and the first end of the second protection element V2. The second ESD device ESD2 is connected in series between the second end of the second protection element V2 and the third end of the control logic module. The first ESD device ESD1 and the first end of the second protection element V2 are connected to the pin SENSOR.

[0032] In this embodiment, the first protection element V1 is used to prevent current from flowing back to the first ESD device ESD1, and the second protection element V2 is used to prevent current from flowing back to the second ESD device ESD2. When the battery is connected correctly and the first ESD device ESD1 and the second ESD device ESD2 are triggered, the first protection element V1 and the second protection element V2 conduct. When the battery is connected reversely, the pin Gnd is at a high potential. At this time, the first protection element V1 and the second protection element V2 are cut off, resulting in the first ESD device ESD1 and the second ESD device ESD2 being cut off, thereby avoiding damage to the first ESD device ESD1 and the second ESD device ESD2 due to large current flowing through.

[0033] Optionally, as Figure 4As shown, the first protection element V1 and the second protection element V2 are in the form of diodes. The first end of the first protection element V1 is the anode of the diode, the second end of the first protection element V1 is the cathode of the diode, the first end of the second protection element V2 is the anode of the diode, and the first end of the second protection element V2 is the cathode of the diode. Those skilled in the art can also select other forms of protection elements that can prevent the reverse flow of ESD current. The first protection element V1 and the second protection element V2 can be of the same form or different forms, which does not affect the protection scope of this application.

[0034] The pin SENSOR is connected to a sensor for detecting sound or air flow. The sensor sends a signal to the control logic module through the pin SENSOR, enabling the control logic module to detect whether there is a smoke inhalation action.

[0035] It should be noted that the first end of the first ESD device ESD1 and the second protection element V2 can also be connected to other Pad (bonded pads encapsulated inside the control chip) pins of the control chip (except for the pin CELL and the pin Gnd), which does not affect the protection scope of this application.

[0036] To improve the flexibility of the control circuit, in some embodiments of this application, the structures of the first ESD device ESD1 and the second ESD device ESD2 include a diode structure, or a ggnmos (gate-grounded NMOS) structure, or a PNP structure.

[0037] Although Figure 4 in, the structures of the first ESD device ESD1 and the second ESD device ESD2 are diode structures, those skilled in the art can also adopt other structures including the ggnmos structure or the PNP structure, etc.

[0038] To ensure the improvement of the reliability of the electronic atomizer, in some embodiments of this application, the control chip further includes:

[0039] The pin USB, connected to the control logic module, is used to enable the control logic module to perform charging management on the battery;

[0040] The pin LED, connected to the control logic module, is used to enable the control logic module to control the LED of the electronic atomizer.

[0041] Those skilled in the art can set other types of pins on the control chip according to actual needs, which does not affect the protection scope of this application.

[0042] To further improve the safety of the electronic atomizer, in some embodiments of this application, the impedance of the heating wire is less than the impedance of the resistor R1.

[0043] In this embodiment, since the current I = V / R and the impedance of the heating wire is less than that of the resistor R1, when the battery is connected reversely, the reverse current mainly conducts through the heating wire, preventing the current flowing into the control chip through the resistor R1 from being too large, thereby avoiding burning out the chip.

[0044] In order to further improve the safety of the electronic atomizer, in some embodiments of the present application, the impedance of the heating wire is 1Ω and the impedance of the resistor is 100Ω, or other values may also be used.

[0045] By applying the above technical solution, the control circuit is integrated on a control chip including pin CELL, pin Vout, and pin Gnd. The control circuit includes a control logic module, a power supply module, a clamping element, a resistor, and an NMOS power transistor. Among them, the control logic module is used to generate a control signal for the electronic atomizer according to a preset control logic, the power supply module is used to supply power to the control logic module, the first end of the control logic module is connected to the first end of the power supply module, the resistor is connected in series between the second end of the power supply module and pin CELL, the second end of the control logic module and the first end of the clamping element are commonly connected to the gate of the NMOS power transistor, the drain of the NMOS power transistor is connected to pin CELL, the source of the NMOS power transistor is connected to pin Vout, the third end of the control logic module and the second end of the clamping element are commonly connected to pin Gnd, both ends of the heating wire are respectively connected to pin Vout and pin Gnd, and the battery of the electronic atomizer is connected between pin CELL and pin Gnd. When the battery of the electronic atomizer is reversely connected, the current flows through the NMOS power transistor, avoiding the out-of-control current from damaging the control chip and improving the safety of the electronic atomizer.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A control circuit for an electronic atomizer, characterized in that, The control circuit is integrated on a control chip including pin CELL, pin Vout, and pin Gnd. The control circuit includes a control logic module, a power supply module, a clamping element, a resistor, and an NMOS power transistor. Among them, the control logic module is used to generate a control signal for the electronic atomizer according to a preset control logic. The power supply module is used to supply power to the control logic module. The first end of the control logic module is connected to the first end of the power supply module. The resistor is connected in series between the second end of the power supply module and pin CELL. The second end of the control logic module and the first end of the clamping element are commonly connected to the gate of the NMOS power transistor. The drain of the NMOS power transistor is connected to pin CELL. The source of the NMOS power transistor is connected to pin Vout. The third end of the control logic module and the second end of the clamping element are commonly connected to pin Gnd. Both ends of the heating wire of the electronic atomizer are respectively connected to pin Vout and pin Gnd. A battery of the electronic atomizer is connected between pin CELL and pin Gnd; wherein, when the positive electrode of the battery is connected to pin Gnd and the negative electrode of the battery is connected to pin CELL, the clamping element clamps a PN junction voltage drop between the gate of the NMOS power transistor and pin Gnd; and, the impedance of the heating wire is less than the impedance of the resistor.

2. The control circuit according to claim 1, characterized in that, The control chip further includes pin SENSOR. Pin SENSOR is connected to the fourth end of the control logic module. The control circuit further includes a first ESD device, a second ESD device, a first protection element, and a second protection element. The first end of the first protection element is connected to the second end of the power supply module. The first ESD device is connected in series between the second end of the first protection element and the first end of the second protection element. The second ESD device is connected in series between the second end of the second protection element and the third end of the control logic module. The first ESD device and the first end of the second protection element are connected to pin SENSOR; wherein, pin SENSOR is used to enable the control logic module to detect whether there is a smoke inhalation action. The first protection element is used to prevent current from flowing back to the first ESD device. The second protection element is used to prevent current from flowing back to the second ESD device.

3. The control circuit according to claim 2, characterized in that, The structures of the first ESD device and the second ESD device include a diode structure, or a ggnmos structure, or a PNP structure.

4. The control circuit according to claim 1, characterized in that, The control chip further includes: pin USB, connected to the control logic module, for enabling the control logic module to perform charging management on the battery; pin LED, connected to the control logic module, for enabling the control logic module to control the LED of the electronic atomizer.

5. An electronic atomizer, characterized in that, including the control circuit according to any one of claims 1-4.

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