Power-off reset circuit and electronic cigarette

Abstract

The invention relates to a power-off reset circuit and an electronic cigarette. The power-off reset circuit comprises an interface, a first switch module, a control module and a second switch module, the interface is used for receiving a conduction control signal under the condition that the interface is connected with external equipment, the first switch module is connected with the interface and is conducted under the condition that the conduction control signal is received, and the control module is connected with the first switch module and an external power supply. When the first switch module is switched on, a power-off control signal is output according to the power supply voltage, a power-on control signal is output after target time, and when the second switch module is connected with the control module, the external power supply and the controller, the external power supply and the controller are disconnected under the condition that the power-off control signal is received, so that the controller is powered off. When the power-on control signal is received, the connection between the external power supply and the controller is conducted, so that the controller is powered on, the power-off reset function can be started under the condition that the single-chip microcomputer breaks down, and the power-off reset reliability is improved.

Description

Technical Field

[0001] The present application relates to the technical field of power-off reset, and in particular to a power-off reset circuit and an electronic cigarette. Background Art

[0002] At present, in electronic devices with built-in single-chip microcomputers, the reset pin of the single-chip microcomputer is provided with a power-off reset function. In the event of a failure in the electronic device, it is necessary to activate the power-off reset function at the reset pin of the single-chip microcomputer so that the electronic device can be used normally after power-off reset.

[0003] However, when the microcontroller fails, there is a risk that the reset pin will be out of control, causing the power-off reset function to fail to start normally, thereby reducing the reliability of the power-off reset function. Summary of the invention

[0004] Based on this, it is necessary to provide a power-off reset circuit and an electronic cigarette that can normally start the power-off reset function and improve the reliability of power-off reset when a single-chip microcomputer fails.

[0005] In a first aspect, the present application provides a power-off reset circuit, comprising:

[0006] An interface, used to receive a conduction control signal input by an external device when connected to the external device;

[0007] A first switch module, used to be connected to the interface and to be turned on when receiving the turn-on control signal;

[0008] a control module, configured to be connected to the first switch module and the external power supply, and to output a power-off control signal according to the power supply voltage input by the external power supply when the first switch module is turned on, and to output a power-on control signal after a target time has passed;

[0009] The second switch module is used to connect with the control module, the external power supply and the controller. When receiving the power-off control signal, the second switch module disconnects the connection between the external power supply and the controller to power off the controller. When receiving the power-on control signal, the second switch module connects the connection between the external power supply and the controller to power on the controller.

[0010] In one embodiment, the target time includes a first target time and a second target time, and the control module includes:

[0011] a first control unit, configured to be connected to the first switch module and the external power supply, and to output a first control signal according to the power supply voltage when the first switch module is turned on, and to output a second control signal after the first target time has passed;

[0012] a first switch unit, configured to be connected to the first control unit and the external power supply, to be turned on when receiving the first control signal, and to be turned off when receiving the second control signal;

[0013] A second control unit is used to be connected to the first switch unit and the second switch module, and to output the power-off control signal according to the power supply voltage when the first switch unit is turned on, and to output the power-on control signal after the second target time has passed when the first switch unit is turned off.

[0014] In one embodiment, the first control unit comprises:

[0015] a first voltage-dividing resistor, wherein a first end of the first voltage-dividing resistor is connected to the external power supply, and a second end of the first voltage-dividing resistor is connected to the first switch module, and is used for dividing the power supply voltage by connecting to an equivalent ground through the first switch module when the first switch module is turned on, so as to obtain a first potential energy;

[0016] a first energy storage resistor, wherein a first end of the first energy storage resistor is connected to the external power supply and is used to divide the power supply voltage to obtain a second potential energy when the first switch module is turned on;

[0017] A first energy storage element, wherein the first end of the first energy storage element is connected to the second end of the first voltage-dividing resistor, and the second end of the first energy storage element is connected to the second end of the first energy storage resistor, and is used to store energy according to the charging voltage generated between the first electric potential energy and the second electric potential energy, and output the first control signal, and also to output the second control signal after the first target time has passed.

[0018] In one embodiment, the first switch unit includes:

[0019] A first switch element, wherein a first end of the first switch element is connected to the first control unit, a second end of the first switch element is connected to the external power supply, and a third end of the first switch element is connected to the second control unit. The first switch element is used to conduct the connection between the external power supply and the second control unit when the first control signal is received, and is also used to disconnect the connection between the external power supply and the second control unit when the second control signal is received.

[0020] In one embodiment, the second control unit comprises:

[0021] a second energy storage resistor, wherein a first end of the second energy storage resistor is connected to the first switch unit and the second switch module, and a second end of the second energy storage resistor is grounded, and is used for connecting to the external power supply through the first switch unit when the first switch unit is turned on, so as to divide the power supply voltage;

[0022] A second energy storage element, wherein the first end of the second energy storage element is connected to the second energy storage resistor, the first switch unit, and the second switch module, and the second end of the second energy storage element is grounded, and is used to store energy when the divided power supply voltage is received and output the power-off control signal, and is also used to discharge when the divided power supply voltage is not received and output the power-on control signal after the second target time has passed.

[0023] In one embodiment, the second switch module includes:

[0024] A second switch unit, wherein a first end of the second switch unit is connected to the control module, a second end of the second switch unit is connected to the external power supply, and a third end of the second switch unit is connected to the controller, and is used for disconnecting the connection between the external power supply and the controller to power off the controller when the power-off control signal is received, and for connecting the connection between the external power supply and the controller to power on the controller when the power-on control signal is received.

[0025] In one embodiment, the second switch unit includes:

[0026] A second switch element, wherein a first end of the second switch element is connected to the control module, a second end of the second switch element is connected to the external power supply, and a third end of the second switch element is connected to the controller, and is configured to be cut off when receiving the power-off control signal and to be turned on when receiving the power-on control signal.

[0027] In one embodiment, the first switch module includes:

[0028] A second voltage-dividing resistor, used to be connected to the interface to divide the voltage of the conduction control signal;

[0029] a third switch element, wherein a first end of the third switch element is connected to the second voltage-dividing resistor, a second end of the third switch element is connected to the control module, and a third end of the third switch element is grounded, and is configured to be turned on when receiving the conduction control signal after voltage division;

[0030] A protection resistor, one end of which is connected to the first end of the third switch element, and the other end of which is connected to the third end of the third switch element.

[0031] In one embodiment, the interface includes a charging interface that supports hot-swap functionality.

[0032] In a second aspect, the present application provides an electronic cigarette, comprising:

[0033] the controller; and

[0034] A power-off reset circuit as described in the first aspect.

[0035] The above-mentioned power-off reset circuit and electronic cigarette, when the controller of the device fails, connects to the external device through the interface, and receives the conduction control signal input by the external device when the interface is connected to the external device. When the first switch module receives the conduction control signal, it conducts the connection between the control module and the external power supply. The control module continuously outputs the power-off control signal within the target time according to the power supply voltage input by the external power supply, and outputs the power-on control signal after the target time. When the second switch module receives the power-off control signal, it disconnects the connection between the external power supply and the controller, so that the controller is powered off within the target time. When the second switch module receives the power-on control signal, it conducts the connection between the external power supply and the controller, so that the controller is powered on again after the target time. When the single-chip microcomputer fails, the power-off reset function can be normally started, thereby improving the reliability of the power-off reset. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0037] FIG1 is a block diagram of a power-off reset circuit according to an embodiment of the present invention;

[0038] FIG2 is a block diagram of a power-off reset circuit according to another embodiment;

[0039] FIG3 is a block diagram of a power-off reset circuit according to another embodiment;

[0040] FIG. 4 is a circuit schematic diagram of a power-off reset circuit according to an embodiment.

[0041] Description of reference numerals:

[0042] Power-off reset circuit 100, interface 101, first switch module 102, control module 103, second switch module 104, external device 105, external power supply 106, controller 107;

[0043] A first control unit 201, a first switch unit 202, and a second control unit 203;

[0044] The second switch unit 301 . DETAILED DESCRIPTION

[0045] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0046] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0047] It is understood that the terms "first", "second", etc. used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, without departing from the scope of this application, the first control unit may be referred to as the second control unit, and similarly, the second control unit may be referred to as the first control unit. Both the first control unit and the second control unit are control units, but they are not the same control unit.

[0048] It can be understood that the “connection” in the following embodiments should be understood as “electrical connection”, “communication connection”, etc. if the connected circuits, modules, units, etc. have electrical signals or data transmission between each other.

[0049] It can be understood that “at least one” means one or more, “plurality” means two or more, and “at least a portion of an element” means a part or all of an element.

[0050] When used herein, the singular forms "a", "an", and "said / the" may also include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" and the like specify the presence of stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the relevant listed items.

[0051] The power-off reset circuit provided in the embodiment of the present application is mainly used in the application environment of small devices, such as a rechargeable electronic cigarette. The internal and external structures of the small device are relatively small. Therefore, the power-off reset circuit needs to be as simple as possible and not occupy too much space.

[0052] In the related art, many devices rely on the reset pin of the microcontroller to implement the power-off reset function when a fault occurs. However, when the microcontroller fails, there is a risk that the reset pin will be uncontrolled, resulting in the power-off reset function failing to start normally, reducing the reliability of the power-off reset function.

[0053] In addition, the reset pin of the microcontroller is generally provided with a power-off reset circuit, and a push button switch is provided on the power-off reset circuit, and the push button switch is provided on the housing of the device. When in use, the power-off reset function can be directly triggered by pressing the push button switch, which realizes convenience. However, setting a push button switch often requires occupying the structural space of the device, thereby affecting the ID design of the product.

[0054] Based on this, the present application provides a power-off reset circuit and an electronic cigarette, which can start the power-off reset function when a single-chip microcomputer fails, thereby improving the reliability of power-off reset, and does not need to occupy the external structural space of the device, but only occupies a small part of the internal structural space of the device.

[0055] In an exemplary embodiment, as shown in FIG1 , the power-off reset circuit 100 includes an interface 101, a first switch module 102, a control module 103, and a second switch module 104. The interface 101 is used to receive a conduction control signal input by the external device 105 when connected to the external device 105, the first switch module 102 is used to connect to the interface 101, and conduct when receiving the conduction control signal, the control module 103 is used to connect to the first switch module 102 and the external power supply 106, and output a power-off control signal according to the power supply voltage input by the external power supply 106 when the first switch module 102 is conducted, and output a power-on control signal after a target time has passed, and the second switch module 104 is used to connect to the control module 103, the external power supply 106, and the controller 107, and disconnect the connection between the external power supply 106 and the controller 107 when receiving the power-off control signal, so that the controller 107 is powered off, and conduct the connection between the external power supply 106 and the controller 107 when receiving the power-on control signal, so that the controller 107 is powered on.

[0056] Optionally, when a failure occurs in the controller 107 of the device, the external device 105 is connected via the interface 101. When the interface 101 is connected to the external device 105, the interface 101 receives a conduction control signal input by the external device 105. When the first switch module 102 receives the conduction control signal, it conducts the connection between the control module 103 and the external power supply 106. The control module 103 continuously outputs a power-off control signal within a target time according to the power supply voltage input by the external power supply 106, and outputs a power-on control signal after the target time has passed. When the second switch module 104 receives the power-off control signal, it disconnects the connection between the external power supply 106 and the controller 107, so that the controller 107 is powered off within the target time. When the second switch module 104 receives the power-on control signal, it conducts the connection between the external power supply 106 and the controller 107, so that the controller 107 is powered on again after the target time has passed. In the case of a failure of the single-chip microcomputer, the power-off reset function can be normally started, thereby improving the reliability of the power-off reset.

[0057] Among them, the power-off reset circuit 100 is connected to the power input pin of the controller 107, and the power-off reset circuit 100 is set at the power input pin of the controller 107. When the controller 107 fails, the controller 107 is powered off by disconnecting the connection between the controller 107 and the external power supply 106, and the controller 107 is powered on again by reconnecting the connection between the controller 107 and the external power supply 106. The whole process realizes the power-off reset of the controller 107, and can realize the power-off reset without going through the reset pin of the controller 107, and then when the controller 107 fails, the controller 107 can still be stably reset by power-off, thereby improving the stability of the power-off reset of the device.

[0058] In an exemplary embodiment, as shown in FIG. 1 , the interface 101 includes a charging interface supporting a hot-swap function.

[0059] Among them, interface 101 includes interfaces originally designed in the device, such as: a charging interface of the device, a data transmission interface of the device, and other interfaces of the device. The types of interface 101 may include: a USB interface, a type-c interface, a type-b interface, etc. Interface 101 is not specifically limited in this application.

[0060] Optionally, the design of the entire power-off reset circuit 100 can be implemented on the basis of retaining the original design of the device, without occupying the external structural space of the device. It only needs to build a circuit into the device. Moreover, the internal space occupied is not large. It can realize the power-off reset function without occupying the structural space, and reduce the impact of the overall ID design of the product.

[0061] In an exemplary embodiment, the interface 101 is a charging interface of the device. When the external device 105 is inserted into the interface 101 for charging, the charging voltage input by the external device 105 is the conduction control signal. When the first switch module 102 receives the conduction control signal, it conducts the connection between the control module 103 and the external power supply 106. The control module 103 continuously outputs the power-off control signal within the target time according to the power voltage input by the external power supply 106, and outputs the power-on control signal after the target time. When the second switch module 104 receives the power-off control signal, it disconnects the connection between the external power supply 106 and the controller 107, so that the controller 107 is powered off within the target time. When the second switch module 104 receives the power-on control signal, it conducts the connection between the external power supply 106 and the controller 107, so that the controller 107 is powered on again after the target time. In the case of a failure of the single-chip microcomputer, the power-off reset function can be started by inserting an external device, thereby improving the reliability of the power-off reset.

[0062] In an exemplary embodiment, as shown in FIG2 , the target time includes a first target time and a second target time, and the control module 103 includes: a first control unit 201, a first switch unit 202, and a second control unit 203. The first control unit 201 is used to connect with the first switch module 102 and the external power supply 106, and output a first control signal according to the power supply voltage when the first switch module 102 is turned on, and output a second control signal after the first target time has passed. The first switch unit 202 is used to connect with the first control unit 201 and the external power supply 106, and turn on when receiving the first control signal, and is also used to turn off when receiving the second control signal. The second control unit 203 is used to connect with the first switch unit 202 and the second switch module 104, and output a power-off control signal according to the power supply voltage when the first switch unit 202 is turned on, and is also used to output a power-on control signal after the second target time has passed when the first switch unit 202 is turned off.

[0063] The first target time includes the time when the first switch unit 202 is turned on, and the sum of the first target time and the second target time is the time when the controller 107 is powered off.

[0064] Optionally, when the first switch module 102 is turned on, the connection between the external power supply 106 and the first control unit 201 is turned on through the first switch module 102, the first control unit 201 receives the power supply voltage input by the external power supply 106, and outputs a first control signal according to the power supply voltage within a first target time, the first switch unit 202 continues to receive the first control signal within the first target time, the first switch unit 202 continues to be turned on within the first target time, and when the first switch unit 202 is turned on, the connection between the external power supply 106 and the second control unit 203 is turned on through the first switch unit 202, the second control unit 203 receives the power supply voltage within the first target time, and continuously generates and outputs a power-off control signal according to the power supply voltage. In addition, the first control unit 201 outputs a second control signal after the first target time, the first switch unit 202 receives the second control signal after the first target time, and the first switch unit 202 is cut off after the first target time. When the first switch unit 202 is cut off, the connection between the external power supply 106 and the second control unit 203 is disconnected by the first switch unit 202. The second control unit 203 cannot receive the power supply voltage after the first target time, and generates and outputs a power-on control signal after the second target time, which can accurately control the output of the power-off reset control signal, thereby improving the stability of the power-off reset of the device.

[0065] In an exemplary embodiment, as shown in FIG3 , the second switch module 104 includes: a second switch unit 301, a first end of the second switch unit 301 is connected to the control module 103, a second end of the second switch unit 301 is connected to the external power supply 106, and a third end of the second switch unit 301 is connected to the controller 107. The second switch unit 301 is used to disconnect the connection between the external power supply 106 and the controller 107 when a power-off control signal is received, so as to power off the controller 107, and to connect the connection between the external power supply 106 and the controller 107 when a power-on control signal is received, so as to power on the controller 107.

[0066] Optionally, the second switch unit 301 is cut off when receiving a power-off control signal. When the second switch unit 301 is cut off, the connection between the external power supply 106 and the controller 107 is disconnected, thereby powering off the controller 107. The second switch unit 301 is turned on when receiving a power-on control signal. When the second switch unit 301 is turned on, the connection between the external power supply 106 and the controller 107 is turned on, thereby powering on the controller 107 again. The connection between the microcontroller and the power supply can be controlled to start and stop the power-off reset function, thereby improving the reliability of the power-off reset.

[0067] In an exemplary embodiment, as shown in FIG. 4 , the first control unit 201 includes: a first voltage-dividing resistor, a first energy storage resistor, and a first energy storage element.

[0068] The first end of the first voltage-dividing resistor is connected to the external power supply 106, and the second end of the first voltage-dividing resistor is connected to the first switch module 102, and is used to divide the power supply voltage to obtain the first potential energy when the first switch module 102 is turned on, through the first switch module 102 being turned on and connected to the equivalent ground. The first end of the first energy storage resistor is connected to the external power supply 106, and is used to divide the power supply voltage to obtain the second potential energy when the first switch module 102 is turned on. The first end of the first energy storage element is connected to the second end of the first voltage-dividing resistor, and the second end of the first energy storage element is connected to the second end of the first energy storage resistor, and is used to store energy according to the charging voltage generated between the first potential energy and the second potential energy, and output a first control signal, and is also used to output a second control signal after a first target time.

[0069] The external power source 106 is the power source VDD in FIG. 4 , the first voltage divider resistor is the resistor R3 in FIG. 4 , the first energy storage resistor is the resistor R4 in FIG. 4 , and the first energy storage element is the capacitor C1 in FIG. 4 .

[0070] Optionally, when the first switch module 102 is turned on, the connection between the first voltage-dividing resistor and the equivalent ground is turned on by the first switch module 102, so that a current loop is formed in the internal circuit of the first control unit 201, and the power supply voltage is divided by the first voltage-dividing resistor to obtain the first electric potential energy of the first end of the first energy storage element, and the power supply voltage is divided by the first energy storage resistor to obtain the second electric potential energy of the second end of the first energy storage element. Since the electric potential energies at both ends of the first energy storage element are different, a charging voltage is generated, and the first energy storage element is charged and stores energy according to the charging voltage. The first energy storage element continuously outputs the first control signal during the charging process. The first energy storage element completes energy storage after the first target time and outputs the second control signal, which can provide a trigger signal to accurately control the output of the control signal of the power-off reset, thereby improving the stability of the power-off reset of the device.

[0071] In an exemplary embodiment, as shown in FIG4 , the first switch unit 202 includes: a first switch element, a first end of the first switch element is connected to the first control unit 201, a second end of the first switch element is connected to the external power supply 106, and a third end of the first switch element is connected to the second control unit 203, and the first switch element is used to connect the external power supply 106 and the second control unit 203 when a first control signal is received, and is also used to disconnect the connection between the external power supply 106 and the second control unit 203 when a second control signal is received.

[0072] The first switch element is the P-channel MOSFET tube Q2 in FIG. 4 .

[0073] Optionally, the first switch element is turned on when receiving a first control signal, so that the connection between the external power supply 106 and the second control unit 203 is turned on for a first target time. After the first target time, the first switch element receives a second control signal and is turned off, so that the connection between the external power supply 106 and the second control unit 203 is disconnected. The output of the control signal of power-off reset can be automatically triggered by a switch element under corresponding conditions, which simplifies the structural design and reduces the design cost of the circuit.

[0074] In an exemplary embodiment, as shown in FIG. 4 , the second control unit 203 includes: a second energy storage resistor and a second energy storage element.

[0075] The first end of the second energy storage resistor is connected to the first switch unit 202 and the second switch module 104, and the second end of the second energy storage resistor is grounded, and is used to connect to the external power supply 106 through the first switch unit when the first switch unit 202 is turned on to divide the power supply voltage.

[0076] The first end of the second energy storage element is connected to the second energy storage resistor, the first switch unit 202 and the second switch module 104, and the second end of the second energy storage element is grounded. It is used to store energy when receiving the divided power supply voltage and output a power-off control signal, and is also used to discharge when not receiving the divided power supply voltage and output a power-on control signal after a second target time.

[0077] The second energy storage resistor is the resistor R5 in FIG. 4 , and the second energy storage element is the capacitor C2 in FIG. 4 .

[0078] Optionally, when the first switch unit 202 is turned on, the connection between the second energy storage resistor and the external power supply 106 is turned on within the first target time, the second energy storage resistor divides the power supply voltage, and when the second energy storage element receives the divided power supply voltage, the divided power supply voltage forms an equivalent potential difference with the ground, the second energy storage resistor is charged and stores energy, and the second energy storage resistor continuously outputs a power-off control signal during the charging process. After the first target time, the first switch unit 202 is turned off, so that the connection between the second energy storage resistor and the external power supply 106 is disconnected, the second energy storage element does not receive the divided power supply voltage, and the second energy storage element is discharged. During the discharge process of the second energy storage element, the energy storage of the second energy storage element is not lower than a preset threshold within the second target time, and the second energy storage element still outputs a power-off control signal. After the second target time, the energy storage of the second energy storage element is lower than the preset threshold, and the second energy storage element outputs a power-on control signal, which can accurately control the power-off and reset of the microcontroller, thereby improving the reliability of power-off reset of the device.

[0079] In an exemplary embodiment, as shown in Figure 4, the second switch unit 301 includes: a second switch element, a first end of the second switch element is connected to the control module 103, a second end of the second switch element is connected to the external power supply 106, and a third end of the second switch element is connected to the controller 107, which is used to be cut off when a power-off control signal is received, and turned on when a power-on control signal is received.

[0080] The controller 107 is the controller U1 in FIG. 4 , and the second switch element is the P-channel MOSFET tube Q3 in FIG. 4 .

[0081] Optionally, the second switch element receives a power-off control signal and is cut off within the sum of the first target time and the second target time, so that the connection between the controller 107 and the external power supply 106 is disconnected, and the controller 107 is powered off. After the sum of the first target time and the second target time, the second switch element receives a power-on control signal and is turned on, so that the connection between the controller 107 and the external power supply 106 is turned on, and the controller 107 is powered on again. The connection between the microcontroller and the power supply can be automatically controlled by a trigger signal to realize the startup and shutdown of the power-off reset function, thereby improving the reliability of the power-off reset.

[0082] In an exemplary embodiment, as shown in FIG4 , the first switch module 102 includes: a second voltage-dividing resistor, a third switch element, and a protective resistor. The second voltage-dividing resistor is used to connect to the interface 101 to divide the conduction control signal. The first end of the third switch element is connected to the second voltage-dividing resistor, the second end of the third switch element is connected to the control module 103, and the third end of the third switch element is grounded, and is used to conduct when receiving the conduction control signal after voltage division. One end of the protective resistor is connected to the first end of the third switch element, and the other end of the protective resistor is connected to the third end of the third switch element.

[0083] The interface 101 is the VBUS interface in FIG. 4 , the second voltage-dividing resistor is the resistor R1 in FIG. 4 , the third switch element is the NPN transistor Q1 in FIG. 4 , and the protection resistor is the resistor R2 in FIG. 4 .

[0084] Optionally, when the second voltage-dividing resistor receives the on-control signal, it divides the voltage of the on-control signal, and the third switch element is turned on when receiving the on-control signal after the voltage division, so that the connection between the first control unit 201 and the equivalent ground is turned on, thereby forming a loop in the circuit within the first control unit 201, which can directly trigger the power-off reset circuit to start the power-off reset function when the interface is connected, thereby improving the reliability of the power-off reset.

[0085] In an exemplary embodiment, as shown in FIG. 4 , when the interface 101 is not plugged into an external device, the VBUS signal is at a low level, the transistor Q1 is turned off, the voltages to ground at both ends of the capacitor C1 are both the power supply voltage VDD, the PMOS tube Q2 is in a cut-off state, and the S-pole voltage of the PMOS tube Q3 is VDD, and the G-pole voltage of the PMOS tube Q3 is pulled down by the resistor R5, therefore, the PMOS tube Q3 is turned on, and after the power supply voltage VDD forms a VDD_MCU signal through the PMOS tube Q3, the controller U1 is powered through the VDD_MCU signal, so that the controller U1 works normally.

[0086] When the interface 101 is plugged into an external device, the VBUS signal is at a high level, the transistor Q1 is turned on, the capacitor C1 is charged through the resistor R4, the G pole voltage of the PMOS tube Q2 will slowly increase, and the S pole of the PMOS tube Q2 is always the VDD voltage, so the PMOS tube Q2 will be turned on briefly, and during the short-term on period of the PMOS tube Q2, the capacitor C2 will be charged to the VDD voltage, at this time, the G pole of the PMOS tube Q3 is the VDD voltage, the PMOS tube Q3 is turned off, the controller U1 has no power input, and the controller U1 stops working. The PMOS tube Q2 is turned off after being turned on briefly, and the voltage on the capacitor C2 will be discharged through the resistor R5 after the PMOS tube Q2 is turned off. When the voltage on the capacitor C2 is discharged to a certain voltage value, the PMOS tube Q3 will enter the on state again, the controller U1 will be powered on again, and the power-on reset action will be performed, which can start the power-off reset function in the event of a fault in the single-chip microcomputer, thereby improving the reliability of the power-off reset.

[0087] Among them, the VDD_MCU signal in FIG4 is the output signal after the PMOS tube Q3 is turned on, that is, the signal used to power the controller 107. When the USB is inserted, the single chip will perform the actions of powering off and re-powering on. The power-off time can be adjusted by the resistors R5 and C2. When the power-off time needs to be extended, the value of the resistor R5 or the capacitor C2 can be increased. When the power-off time needs to be reduced, the value of the resistor R5 or the capacitor C2 can be appropriately reduced. The specific parameters can be adjusted according to the actual project, and the use is more flexible. In addition, the time when the PMOS tube Q2 is turned on is related to the parameters of the resistor R4, the capacitor C1 and the PMOS tube Q2.

[0088] In addition, the present application also proposes an electronic cigarette, including: a controller, and a power-off reset circuit as described in any of the above embodiments.

[0089] Among them, the electronic cigarette may include a rechargeable HNB smoking device. The full name of HNB is Heated Not Burned. HNB smoking devices are a new type of alternative smoking products. Also, the interface provided in the power-off reset circuit may include the charging interface originally designed for the electronic cigarette, or other interfaces. The interface provided in the power-off reset circuit is not specifically limited in this application. In addition, the controller in the electronic cigarette or HNB smoking device may be a single-chip microcomputer. The controller is not specifically limited in this application, and the controller is mainly used to control the heating process of the special tobacco.

[0090] Optionally, when the electronic cigarette is out of control due to external conditions, the electronic cigarette can be inserted into a charger to connect the power-off reset circuit to the charger. After the power-off reset circuit receives the conduction control signal input by the charger, the controller inside the electronic cigarette can be powered on and reset, which can improve the stability of the power-off reset of the electronic cigarette. In addition, there is no need to set a push button switch, which saves external resources of the electronic cigarette and reduces the design cost of the electronic cigarette.

[0091] It can be understood that the above-mentioned power-off reset circuit and electronic cigarette can also adopt other forms, not limited to the forms mentioned in the above embodiments, as long as they can achieve the function of starting the power-off reset function and improving the reliability of the power-off reset when a single-chip microcomputer fails.

[0092] In the description of this specification, the description with reference to the terms "some embodiments", "other embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic description of the above terms does not necessarily refer to the same embodiment or example.

[0093] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0094] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A power-off reset circuit, characterized in that: include: An interface, used to receive a conduction control signal input by an external device when connected to the external device; A first switch module, used to be connected to the interface and to be turned on when receiving the turn-on control signal; a control module, configured to be connected to the first switch module and the external power supply, and to output a power-off control signal according to the power supply voltage input by the external power supply when the first switch module is turned on, and to output a power-on control signal after a target time has passed; The second switch module is used to connect with the control module, the external power supply and the controller. When receiving the power-off control signal, the second switch module disconnects the connection between the external power supply and the controller to power off the controller. When receiving the power-on control signal, the second switch module connects the connection between the external power supply and the controller to power on the controller.

2. The power-off reset circuit according to claim 1, characterized in that: The target time includes a first target time and a second target time, and the control module includes: a first control unit, configured to be connected to the first switch module and the external power supply, and to output a first control signal according to the power supply voltage when the first switch module is turned on, and to output a second control signal after the first target time has passed; a first switch unit, configured to be connected to the first control unit and the external power supply, to be turned on when receiving the first control signal, and to be turned off when receiving the second control signal; A second control unit is used to be connected to the first switch unit and the second switch module, and to output the power-off control signal according to the power supply voltage when the first switch unit is turned on, and to output the power-on control signal after the second target time has passed when the first switch unit is turned off.

3. The power-off reset circuit according to claim 2, characterized in that: The first control unit comprises: a first voltage-dividing resistor, wherein a first end of the first voltage-dividing resistor is connected to the external power supply, and a second end of the first voltage-dividing resistor is connected to the first switch module, and is used for dividing the power supply voltage by connecting to an equivalent ground through the first switch module when the first switch module is turned on, so as to obtain a first potential energy; a first energy storage resistor, wherein a first end of the first energy storage resistor is connected to the external power supply and is used to divide the power supply voltage to obtain a second potential energy when the first switch module is turned on; A first energy storage element, wherein the first end of the first energy storage element is connected to the second end of the first voltage-dividing resistor, and the second end of the first energy storage element is connected to the second end of the first energy storage resistor, and is used to store energy according to the charging voltage generated between the first electric potential energy and the second electric potential energy, and output the first control signal, and also to output the second control signal after the first target time has passed.

4. The power-off reset circuit according to claim 2, characterized in that: The first switch unit comprises: A first switch element, wherein a first end of the first switch element is connected to the first control unit, a second end of the first switch element is connected to the external power supply, and a third end of the first switch element is connected to the second control unit. The first switch element is used to conduct the connection between the external power supply and the second control unit when the first control signal is received, and is also used to disconnect the connection between the external power supply and the second control unit when the second control signal is received.

5. The power-off reset circuit according to claim 2, characterized in that: The second control unit comprises: a second energy storage resistor, wherein a first end of the second energy storage resistor is connected to the first switch unit and the second switch module, and a second end of the second energy storage resistor is grounded, and is used for connecting to the external power supply through the first switch unit when the first switch unit is turned on, so as to divide the power supply voltage; A second energy storage element, wherein the first end of the second energy storage element is connected to the second energy storage resistor, the first switch unit, and the second switch module, and the second end of the second energy storage element is grounded, and is used to store energy when the divided power supply voltage is received and output the power-off control signal, and is also used to discharge when the divided power supply voltage is not received and output the power-on control signal after the second target time has passed.

6. The power-off reset circuit according to claim 1, characterized in that: The second switch module comprises: A second switch unit, wherein a first end of the second switch unit is connected to the control module, a second end of the second switch unit is connected to the external power supply, and a third end of the second switch unit is connected to the controller, and is used for disconnecting the connection between the external power supply and the controller to power off the controller when the power-off control signal is received, and for connecting the connection between the external power supply and the controller to power on the controller when the power-on control signal is received.

7. The power-off reset circuit according to claim 6, characterized in that: The second switch unit comprises: A second switch element, wherein a first end of the second switch element is connected to the control module, a second end of the second switch element is connected to the external power supply, and a third end of the second switch element is connected to the controller, and is configured to be cut off when receiving the power-off control signal and to be turned on when receiving the power-on control signal.

8. The power-off reset circuit according to claim 1, characterized in that: The first switch module comprises: A second voltage-dividing resistor, used to be connected to the interface to divide the voltage of the conduction control signal; a third switch element, wherein a first end of the third switch element is connected to the second voltage-dividing resistor, a second end of the third switch element is connected to the control module, and a third end of the third switch element is grounded, and is configured to be turned on when receiving the conduction control signal after voltage division; A protection resistor, one end of which is connected to the first end of the third switch element, and the other end of which is connected to the third end of the third switch element.

9. The power-off reset circuit according to claim 1, characterized in that: The interface includes a charging interface that supports hot-plugging function.

10. An electronic cigarette, characterized in that: include: Controller; and A power-off reset circuit as claimed in any one of claims 1 to 9.

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