Wake-up circuit and electronic device

Abstract

This application relates to a wake-up circuit and electronic device. The wake-up circuit includes: an external power supply interface; an internal power supply interface; a main control chip, which includes an interrupt pin, a power supply pin, and a ground pin; the power supply pin is connected to the positive terminal of the internal power supply interface and is also used to connect to the positive terminal of the external power supply interface; the ground pin is connected to the negative terminal of the internal power supply interface; a pull-up unit, one end of which is connected to the interrupt pin, and the other end of which is connected to the power supply pin; and a pull-down unit, one end of which is connected to the negative terminal of the external power supply interface, and the other end of which is connected to the interrupt pin; the main control chip is woken up when the potential of the interrupt pin changes. Through this application, automatic wake-up of the main control chip when it is connected to an external power supply is achieved via the interrupt pin, reliably waking up the main control chip from its sleep state without increasing additional standby power consumption.

Description

Technical Field

[0001] This application relates to the field of circuit electronics technology, and in particular to a wake-up circuit and electronic device. Background Technology

[0002] In order to extend battery life and reduce standby power consumption, some electronic devices, especially portable ones, typically put their main control chip and other peripheral loads into a low-power sleep mode when not in use. However, when a user charges the electronic device, a mechanism is needed to wake up the sleep-state main control chip to perform human-computer interaction tasks such as charging management and status display.

[0003] In the existing technology, realizing this wake-up function may require setting up detection elements or detection circuits in electronic devices. However, such detection elements or detection circuits usually have a certain static power consumption, which to some extent violates the original intention of entering sleep mode to save power to the maximum extent.

[0004] Therefore, how to reliably wake up the main control chip from its sleep state without increasing standby power consumption is a technical problem that urgently needs to be solved. Utility Model Content

[0005] Therefore, it is necessary to provide a wake-up circuit and electronic device to reliably wake up the main control chip in a dormant state without increasing additional standby power consumption.

[0006] Firstly, a wake-up circuit is provided, comprising:

[0007] External power supply interface;

[0008] Internal power supply interface;

[0009] The main control chip includes an interrupt pin, a power supply pin, and a ground pin; the power supply pin is connected to the positive terminal of the internal power supply interface, and the power supply pin is also used to connect to the positive terminal of the external power supply interface; the ground pin is connected to the negative terminal of the internal power supply interface.

[0010] A potential pull-up unit, one end of which is connected to the interrupt pin and the other end of which is connected to the power supply pin;

[0011] A potential pull-down unit is provided, one end of which is connected to the negative terminal of the external power supply interface, and the other end of which is connected to the interrupt pin; the main control chip is woken up when the potential of the interrupt pin changes.

[0012] In one embodiment, the wake-up circuit further includes a switching unit, the main control chip further includes a control pin, the first end of the switching unit is connected to the negative terminal of the external power supply interface and the potential pull-down unit respectively, the second end of the switching unit is connected to the negative terminal of the internal power supply interface and the ground pin respectively, and the control end of the switching unit is connected to the control pin;

[0013] The main control chip outputs a control signal to the switching unit through the control pin to control the conduction state of the switching unit.

[0014] In one embodiment, the switching unit includes a first switching transistor, the first terminal of which is connected to the negative terminal of the external power supply interface and the pull-down unit, the second terminal of which is connected to the negative terminal of the internal power supply interface and the ground pin, and the control terminal of which is connected to the control pin.

[0015] In one embodiment, the first switching transistor is an N-type insulated-gate field-effect transistor or a P-type insulated-gate field-effect transistor.

[0016] In one embodiment, the control pin includes a first control pin and a second control pin, the switching unit includes a second switching transistor and a third switching transistor, the first terminal of the second switching transistor is connected to the negative terminal of the external power supply interface and the potential pull-down unit, the second terminal of the second switching transistor is connected to the second terminal of the third switching transistor, the first terminal of the third switching transistor is connected to the negative terminal of the internal power supply interface and the ground pin, the control terminal of the second switching transistor is connected to the first control pin, and the control terminal of the third switching transistor is connected to the second control pin.

[0017] In one embodiment, both the second and third switching transistors are field-effect transistors, and the body diodes of the second and third switching transistors have opposite conduction directions.

[0018] In one embodiment, the potential pull-down unit includes a first resistor, one end of which is connected to the negative terminal of the external power supply interface, and the other end of which is connected to the interrupt pin.

[0019] In one embodiment, the potential pull-up unit includes a second resistor, one end of which is connected to the interrupt pin and the other end of which is connected to the power supply pin.

[0020] In one embodiment, the external power supply interface is a Universal Serial Bus interface.

[0021] In a second aspect, an electronic device is provided, including an internal power supply and a wake-up circuit according to any one of the first aspects above, wherein the internal power supply is connected to the internal power supply interface.

[0022] The wake-up circuit provided in this application includes a main control chip, an external power supply interface, an internal power supply interface, a pull-down unit, and a pull-up unit. The main control chip includes an interrupt pin, a power supply pin, and a ground pin. The power supply pin is connected to the positive terminal of the internal power supply interface and is also used to connect to the positive terminal of the external power supply interface; the ground pin is connected to the negative terminal of the internal power supply interface; one end of the pull-up unit is connected to the interrupt pin, and the other end is connected to the power supply pin; one end of the pull-down unit is connected to the negative terminal of the external power supply interface, and the other end is connected to the interrupt pin; the main control chip is woken up when the potential of the interrupt pin changes. It can be seen that when the external power supply interface is not connected to an external power supply, the interrupt pin remains at a high potential due to the presence of the pull-up unit. When the external power supply interface is connected to an external power supply, the loop formed by the positive terminal of the external power supply interface - the power supply pin - the pull-up unit - the pull-down unit - the negative terminal of the external power supply interface is completed. The pull-down unit pulls down the potential of the interrupt pin, causing a change in the potential of the interrupt pin and waking up the main control chip. The technical solution provided in this application allows the internal power supply connected to the internal power supply interface of the main control chip to maintain the standby power consumption of the main control chip when the main control chip is in sleep mode. When the external power supply is connected, the main control chip is automatically woken up by the potential change of the interrupt pin. There is no need to rely on other detection elements or detection circuits with static power consumption. The main control chip in sleep mode can be reliably woken up without increasing the standby power consumption. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the wake-up circuit in one embodiment;

[0025] Figure 2 This is a schematic diagram of the wake-up circuit in another embodiment;

[0026] Figure 3 This is a schematic diagram of the circuit structure of the wake-up circuit in one embodiment;

[0027] Figure 4 This is a schematic diagram of the circuit structure of the wake-up circuit in another embodiment;

[0028] Figure 5 This is a schematic diagram of the structure of an electronic device in one embodiment.

[0029] Explanation of reference numerals in the attached figures:

[0030] 100. Wake-up circuit; 110. External power supply interface; 120. Internal power supply interface; 130. Main control chip; 140. Pull-up unit; 150. Pull-down unit; 160. Switching unit; 200. External power supply; 300. Internal power supply; 400. Electronic equipment;

[0031] VCC, power supply pin; GND, ground pin; PIN_A, interrupt pin; PIN_B, control pin; PIN_B1, first control pin; PIN_B2, second control pin; R1, first resistor; R2, second resistor; Q1, first switching transistor; Q2, second switching transistor; Q3, third switching transistor; D1, first body diode; D2, second body diode. Detailed Implementation

[0032] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0034] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0035] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0036] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.

[0037] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0038] This application provides a wake-up circuit and electronic device, aiming to solve the technical problem that existing electronic devices, especially portable electronic devices that rely on internal energy storage components for standby, may introduce additional static power consumption when woken up from a sleep state by an external power supply. The technical solution provided by this application does not require dedicated detection components or detection circuits; it relies on the electronic device's connection to an external power supply to wake it up. It has a simple structure, low cost, and the wake-up circuit itself does not generate any power consumption when the electronic device is not charging, thus minimizing the standby power consumption of the electronic device.

[0039] Reference Figure 1 This application provides a wake-up circuit 100, including: an external power supply interface 110, an internal power supply interface 120, a main control chip 130, a potential pull-up unit 140, and a potential pull-down unit 150.

[0040] The main control chip 130 includes an interrupt pin PIN_A, a power supply pin VCC, and a ground pin GND. The power supply pin VCC is connected to the positive terminal of the internal power supply interface 120 and is also used to connect to the positive terminal of the external power supply interface 110. The ground pin GND is connected to the negative terminal of the internal power supply interface 120.

[0041] One end of the pull-up unit 140 is connected to the interrupt pin PIN_A, and the other end of the pull-up unit 140 is connected to the power supply pin VCC.

[0042] One end of the potential pull-down unit 150 is used to connect to the negative terminal of the external power supply interface 110, and the other end of the potential pull-down unit 150 is connected to the interrupt pin PIN_A; the main control chip 130 is woken up when the potential of the interrupt pin PIN_A changes.

[0043] Specifically, the charging wake-up circuit 100 is applied to an electronic device. The external power supply interface 110 is any physical connector or port capable of receiving power from the external power supply 200 of the electronic device, such as a Universal Serial Bus (USB) interface, a DC power socket, etc. The external power supply interface 110 includes at least one positive terminal and one negative terminal. When the external power supply interface 110 is connected to the external power supply 200, the positive terminal of the external power supply interface 110 is connected to the positive terminal of the external power supply 200, and the negative terminal of the external power supply interface 110 is connected to the negative terminal of the external power supply 200. The external power supply 200 can be a USB power supply.

[0044] The internal power supply interface 120 is any physical connector or port capable of receiving electrical energy from the internal power supply 300 of the electronic device. It is understood that the electronic device typically includes an internal power supply 300, which powers components such as the main control chip 130. In some embodiments, the internal power supply 300 has charging and discharging capabilities; for example, the internal power supply 300 is a rechargeable battery.

[0045] The internal power supply interface 120 also includes at least one positive terminal and one negative terminal. When the internal power supply interface 120 is connected to the internal power supply 300, the positive terminal of the internal power supply interface 120 is connected to the positive terminal of the internal power supply 300, and the negative terminal of the internal power supply interface 120 is connected to the negative terminal of the internal power supply 300. Thus, the internal power supply 300 supplies power to the main control chip 130 through the positive and negative terminals of the internal power supply interface 120, as well as the power supply pin VCC and the ground pin GND of the main control chip 130.

[0046] One end of the pull-up unit 140 is connected to the interrupt pin PIN_A, and the other end is connected to the power supply pin VCC. The pull-up unit 140 is used to pull the potential of the interrupt pin PIN_A high under specific conditions.

[0047] One end of the pull-down unit 150 is connected to the negative terminal of the external power supply interface 110, and the other end of the pull-down unit 150 is connected to the interrupt pin PIN_A. The pull-up unit 140 is used to pull the potential of the interrupt pin PIN_A low under specific conditions.

[0048] The main control chip 130 can be an existing core processing unit in an electronic device, or it can be set up independently and connected to an existing processing unit in the electronic device, outputting a corresponding signal to the existing processing unit when it is woken up. For example, the main control chip 130 can be a microcontroller (MCU), a microprocessor (MPU), a system-on-a-chip (SoC), or other programmable logic devices. The power supply pin VCC and the ground pin GND of the main control chip 130 are used to supply power to the main control chip 130. The power supply pin VCC of the main control chip 130 is connected to the positive terminal of the internal power supply interface 120 and the positive terminal of the external power supply interface 110, respectively. The ground pin GND of the main control chip 130 is connected to the negative terminal of the internal power supply interface 120. When the potential of the interrupt pin PIN_A of the main control chip 130 changes, the main control chip 130 is woken up. The interrupt pin PIN_A of the main control chip 130 is connected to one end of the pull-up unit 140 and the other end of the pull-down unit 150.

[0049] Based on the above connection method, the working principle of the wake-up circuit 100 provided in this embodiment is described as follows:

[0050] When the electronic device is not connected to the external power supply 200, the external power supply interface 110 is in a floating state, and the electronic device is powered by the internal power supply 300. At this time, the internal power supply 300 supplies power to the main control chip 130 and other components to enable the electronic device to work normally. When the device is in standby mode, in order to save power, the main control chip 130 enters a low-power sleep mode, and the internal power supply 300 provides standby power to the main control chip 130. In this state, since the negative terminal of the external power supply interface 110 is disconnected, the potential pull-down unit 150 is also actually in a floating state and cannot form an effective pull-down circuit. Therefore, the potential of the interrupt pin PIN_A is completely determined by the potential pull-up unit 140 and is pulled up to the potential of the power supply pin VCC, i.e., the logic high level.

[0051] When the user plugs the external power supply 200 into the external power supply interface 110, the positive terminal of the external power supply 200 supplies power to the power supply pin VCC, while the negative terminal of the external power supply 200 is connected to the corresponding terminal of the pull-down unit 150. At this time, the pull-down loop formed by the positive terminal of the external power supply interface 110 - the power supply pin VCC - the pull-up unit 140 - the pull-down unit 150 - the negative terminal of the external power supply interface 110 is turned on. The pull-up unit 140 and the pull-down unit 150 form a voltage divider circuit. The pull-down unit 150 pulls down the potential of the interrupt pin PIN_A, and the potential of the interrupt pin PIN_A changes from the original logic high level to the logic low level.

[0052] The interrupt pin PIN_A of the main control chip 130 is pre-configured to wake up the main control chip 130 when the potential changes. Specifically, when the potential of the interrupt pin PIN_A of the main control chip 130 changes, the main control chip 130 wakes up from the sleep mode and resumes normal operation.

[0053] With the technical solution provided in this application, when the main control chip 130 is in sleep mode, the internal power supply 300 connected to the internal power supply interface 120 only needs to maintain the standby power consumption of the main control chip 130. When the external power supply 200 is connected, the main control chip 130 is automatically woken up by the potential change of the interrupt pin PIN_A. There is no need to rely on other detection elements or detection circuits with static power consumption. The main control chip 130 in sleep mode can be reliably woken up without increasing the additional standby power consumption.

[0054] In some embodiments, refer to Figure 2 The wake-up circuit 100 also includes a switch unit 160, and the main control chip 130 also includes a control pin PIN_B. The first end of the switch unit 160 is connected to the negative end of the external power supply interface 110 and the potential pull-down unit 150, respectively. The second end of the switch unit 160 is connected to the negative end of the internal power supply interface 120 and the ground pin GND, respectively. The control end of the switch unit 160 is connected to the control pin PIN_B.

[0055] The main control chip 130 outputs a control signal to the switching unit 160 through the control pin PIN_B to control the conduction state of the switching unit 160.

[0056] Specifically, the switching unit 160 is used to establish a corresponding charging circuit when the electronic device 400 is connected to the external power supply 200, so that the external power supply 200 charges the internal power supply 300 through the charging circuit. The switching unit 160 is connected in series between the negative terminal of the external power supply interface 110 and the negative terminal of the internal power supply interface 120. The control terminal of the switching unit 160 is also connected to the control pin PIN_B on the main control chip 130. Based on the control signal issued by the control pin PIN_B, the switching unit 160 changes its own conduction state.

[0057] In this embodiment, when the main control chip 130 sends a first control signal to the switching unit 160 via the control pin PIN_B, the switching unit 160 is turned on. When the main control chip 130 sends a second control signal to the switching unit 160 via the control pin PIN_B, the switching unit 160 is turned off.

[0058] Based on the above connection method, the working principle of the wake-up circuit 100 provided in this embodiment is described as follows:

[0059] Before the main control chip 130 enters sleep mode, a second control signal is sent to the switching unit 160, causing the switching unit 160 to disconnect. At this time, the overall circuit topology is completely consistent with the circuit topology of the previous embodiment.

[0060] When the user plugs the external power supply 200 into the external power supply interface 110, since the current switching unit 160 is still disconnected, the wake-up process of the main control chip 130 is completely consistent with the wake-up process described in the previous embodiment, and will not be repeated here. After the main control chip 130 is woken up, it sends a first control signal to the switching unit 160, causing the switching unit 160 to conduct. At this time, the charging circuit of external power supply 200 - positive terminal of external power supply interface 110 - positive terminal of internal power supply interface 120 - internal power supply 300 - negative terminal of internal power supply interface 120 - negative terminal of external power supply interface 110 - external power supply 200 is connected, and the external power supply 200 charges the internal power supply 300 through this charging circuit. At the same time, the external power supply 200 also supplies power to the power supply pin VCC and the ground pin GND of the main control chip 130, maintaining the normal operation of the main control chip 130.

[0061] The technical solution provided in this embodiment constructs a charging circuit and controls the charging circuit based on the switching unit 160. This achieves reliable wake-up of the main control chip 130 while simultaneously charging the internal power supply 300 through the charging circuit.

[0062] In one feasible embodiment, after the main control chip 130 is woken up, it detects the power status of the internal power supply 300 based on the internally set charging program. If the power status meets the corresponding charging standard, it sends a first control signal to the switching unit 160. For example, the power status of the internal power supply 300 may be the charging voltage, charging temperature, and power level of the internal power supply 300. The charging standard may be that the power level of the internal power supply 300 is less than a preset charging power threshold, the charging voltage of the internal power supply 300 is within a preset charging voltage range, and the charging temperature of the internal power supply 300 is within a preset charging temperature range.

[0063] In one feasible embodiment, after the main control chip 130 is woken up, it detects the power status of the internal power supply 300 based on the internally set charging program. If the power status meets the corresponding disconnect charging standard, it sends a second control signal to the switching unit 160. For example, the power status of the internal power supply 300 may be the charging voltage, charging temperature, and power level of the internal power supply 300. The charging standard may be that the power level of the internal power supply 300 is greater than a preset charging power threshold, or that the charging voltage of the internal power supply 300 is not within a preset charging voltage range, or that the charging temperature of the internal power supply 300 is not within a preset charging temperature range.

[0064] The technical solution provided by the above embodiments can effectively prevent the external power supply 200 from immediately starting to charge the internal power supply 300 upon connection in case of abnormal conditions such as overheating of the internal power supply 300 or abnormal charging voltage. While ensuring charging of the internal power supply 300, the safety of the charging process is guaranteed.

[0065] In some embodiments, refer to Figure 3 The switching unit 160 includes a first switching transistor Q1. The first terminal of the first switching transistor Q1 is connected to the negative terminal of the external power supply interface 110 and the potential pull-down unit 150, respectively. The second terminal of the first switching transistor Q1 is connected to the negative terminal of the internal power supply interface 120 and the ground pin GND, respectively. The control terminal of the first switching transistor Q1 is connected to the control pin PIN_B.

[0066] Specifically, the on / off state of the first switch Q1 is determined by the electrical signal at its control electrode. When the first switch Q1 is on, a charging circuit is formed by the external power supply 200, external power supply interface 110, first switch Q1, internal power supply interface 120, and internal power supply 300, allowing the external power supply 200 to charge the internal power supply 300 through this circuit. The first electrode of the first switch Q1, corresponding to the first terminal of the switching unit 160, is connected to the negative terminal of the external power supply interface 110 and the pull-down unit 150. The second electrode of the first switch Q1, corresponding to the second terminal of the switching unit 160, is connected to the negative terminal of the internal power supply interface 120 and the ground pin GND of the main control chip 130. The control electrode of the first switch Q1, corresponding to the control terminal of the switching unit 160, is connected to the control pin PIN_B of the main control chip 130.

[0067] The specific type of the first switching transistor Q1 is not limited. The first switching transistor Q1 can be a metal-oxide-semiconductor field-effect transistor, an insulated-gate field-effect transistor, or a bipolar junction transistor. The specific type can be determined according to the actual selection.

[0068] The gate is the control electrode of the first switch Q1. The first electrode of the first switch Q1 can be either the source or the drain, and the second electrode can be either the source or the drain. It is sufficient to ensure that when the first switch Q1 is turned on, the charging current in the charging circuit can flow to the internal power supply 300.

[0069] As an example, the first switch Q1 is an N-type metal-oxide-semiconductor field-effect transistor (MOSFET). The drain of the N-type MOSFET serves as the first terminal of the first switch Q1, the source of the N-type MOSFET serves as the second terminal of the first switch Q1, and the gate of the N-type MOSFET serves as the control terminal of the first switch Q1. The main control chip 130 can turn on the N-type MOSFET by applying a high-level first control signal to the gate of the N-type MOSFET, and can turn off the N-type MOSFET by applying a low-level second control signal to the gate of the N-type MOSFET.

[0070] In some embodiments, the first switching transistor Q1 is an N-type insulated-gate field-effect transistor or a P-type insulated-gate field-effect transistor.

[0071] Specifically, when the first switching transistor Q1 is an N-type insulated-gate field-effect transistor, the drain of the N-type insulated-gate field-effect transistor serves as the first terminal of the first switching transistor Q1, and is connected to the negative terminal of the external power supply interface 110 and the potential pull-down unit 150, respectively. The source of the N-type insulated-gate field-effect transistor serves as the second terminal of the first switching transistor, and is connected to the negative terminal of the internal power supply interface 120 and the ground pin GND, respectively. The gate of the N-type insulated-gate field-effect transistor serves as the control terminal of the first switching transistor Q1, and is connected to the control pin PIN_B.

[0072] When the first switching transistor Q1 is a P-type insulated-gate field-effect transistor, the source of the P-type insulated-gate field-effect transistor serves as the first terminal of the first switching transistor Q1, and is connected to the negative terminal of the external power supply interface 110 and the potential pull-down unit 150, respectively. The drain of the P-type insulated-gate field-effect transistor serves as the second terminal of the first switching transistor Q1, and is connected to the negative terminal of the internal power supply interface 120 and the ground pin GND, respectively. The gate of the P-type insulated-gate field-effect transistor serves as the control terminal of the first switching transistor Q1, and is connected to the control pin PIN_B.

[0073] Insulated-gate field-effect transistors (IGFETs) have advantages such as low driving power, fast switching speed, and low on-resistance. Through the technical solution provided in this embodiment, the first switching transistor Q1 is selected as an N-type IGFET or a P-type IGFET, which can reduce the loss of the charging circuit, improve the charging efficiency, and is easily driven directly by the control pin PIN_B of the main control chip 130, simplifying the peripheral circuit design.

[0074] In some embodiments, refer to Figure 4 The control pin PIN_B includes a first control pin PIN_B1 and a second control pin PIN_B2. The switching unit 160 includes a second switch Q2 and a third switch Q3. The first terminal of the second switch Q2 is connected to the negative terminal of the external power supply interface 110 and the potential pull-down unit 150, respectively. The second terminal of the second switch Q2 is connected to the second terminal of the third switch Q3. The first terminal of the third switch Q3 is connected to the negative terminal of the internal power supply interface 120 and the ground pin GND, respectively. The control terminal of the second switch Q2 is connected to the first control pin PIN_B1, and the control terminal of the third switch Q3 is connected to the second control pin PIN_B2.

[0075] Specifically, the switching unit 160 is composed of a second switching transistor Q2 and a third switching transistor Q3. Simultaneously, the control pin PIN_B of the main control chip 130 is correspondingly expanded into a first control pin PIN_B1 and a second control pin PIN_B2. The first terminal of the second switching transistor Q2 is connected to the negative terminal of the external power supply interface 110 and the pull-down unit 150. The first terminal of the third switching transistor Q3 is connected to the negative terminal of the internal power supply interface 120 and the ground pin GND of the main control chip 130. The second terminals of the second switching transistor Q2 and the third switching transistor Q3 are interconnected. The gate of the second switching transistor Q2 is connected to the first control pin PIN_B1, and the gate of the third switching transistor Q3 is connected to the second control pin PIN_B2.

[0076] When the second switch Q2 and the third switch Q3 are turned on, a charging circuit is formed by the external power supply 200 - external power supply interface 110 - second switch Q2 - third switch Q3 - internal power supply interface 120 - internal power supply 300. The external power supply 200 can charge the internal power supply 300 through this charging circuit. Both the second and third switches have unidirectional conduction capability; for example, both the second and third switches are field-effect transistors.

[0077] Unlike the embodiment described above that includes a first switch Q1, this embodiment uses a second switch Q2 and a third switch Q3 as a switching unit 160, and the second terminals of the second switch Q2 and the third switch Q3 are connected to each other. Utilizing the unidirectional conduction capability of the second switch Q2 and the third switch Q3, it is ensured that the corresponding charging circuit can be completely cut off when the switching unit 160 is turned off.

[0078] In some embodiments, both the second and third switching transistors are field-effect transistors, and the body diodes of the second switching transistor Q2 and the third switching transistor Q3 have opposite conduction directions.

[0079] Specifically, due to its physical structure, a standard field-effect transistor (FET) device naturally possesses a parasitic diode between its source and drain, called the body diode. For example... Figure 4 As shown, the second switch Q2 contains a first body diode D1, and the third switch Q3 contains a second body diode D2. The presence of the body diode means that even when the field-effect transistor is turned off, some current may still leak from one terminal to the other.

[0080] Consider a possible scenario, and continue referring to... Figure 4 Assume that the switching unit 160 includes a third switching transistor Q3, but does not include the second switching transistor Q2 (i.e., assume...). Figure 4 (The second switching transistor Q2 is short-circuited). When the internal power supply 300 is fully charged, the main control chip 130 attempts to turn off the third switching transistor Q3 to stop charging. However, due to the presence of the second body diode D2 of the third switching transistor Q3, the charging circuit still exists, and the charging current cannot be completely cut off, causing the external power supply 200 to continue charging the internal power supply 300, which may lead to overcharging and damage to the internal power supply 300.

[0081] Consider another possible scenario, and continue to refer to Figure 4 Assume that the switching unit 160 includes the second switching transistor Q2, but does not include the third switching transistor Q3 (i.e., assume...). Figure 4 (The third switch Q3 is short-circuited). When the electronic device is powered by the internal power supply 300, the main control chip 130 attempts to turn off the second switch Q2 to stop charging. However, due to the presence of the first body diode D1 of the second switch Q2, the charging circuit still exists, and the discharge current cannot be completely cut off. If the external power supply interface 110 is connected to a grounded but unpowered device, the internal power supply 300 will continue to discharge, causing power loss in the internal power supply 300, and in severe cases, even leading to over-discharge of the internal power supply 300.

[0082] To solve the above problem, the body diodes of the second switch Q2 and the third switch Q3 are configured with opposite conduction directions, and the conduction states of the second switch Q2 and the third switch Q3 are the same. At this time, when the main control chip 130 simultaneously turns off the second switch Q2 and the third switch Q3 through the first control pin PIN_B1 and the second control pin PIN_B2, the charging / discharging current leaking through the body diode of either MOSFET will be cut off by the body diode of the other MOSFET, thus ensuring a complete shutdown of the charging circuit.

[0083] The technical solution provided in this embodiment, by utilizing the reverse series connection of the body diodes of the second switch Q2 and the third switch Q3, fundamentally solves the problem that a single field-effect transistor cannot bidirectionally block current. This achieves complete disconnection of the charging circuit, effectively preventing overcharging / over-discharging of the internal power supply 300 and improving the safety and reliability of power management in the electronic device 400.

[0084] In some embodiments, the potential pull-down unit 150 includes a first resistor R1, one end of which is connected to the negative terminal of the external power supply interface 110, and the other end of which is connected to the interrupt pin PIN_A.

[0085] Specifically, the pull-down unit 150 can be composed of a first resistor R1, one end of which is connected to the negative terminal of the external power supply interface 110, and the other end of which is connected to the interrupt pin PIN_A. In some embodiments, such as Figure 3 and Figure 4 As shown, the wake-up circuit 100 includes a switching unit 160, and one end of the first resistor R1 is also connected to the first end of the switching unit 160.

[0086] When the external power supply 200 is connected, the first resistor R1 and the potential pull-up unit 140 form a voltage divider circuit. The resistance value of the first resistor R1 can be set by those skilled in the art according to the actual situation, as long as it can ensure that the potential of the interrupt pin PIN_A is lower than the logic low level threshold of the main control chip 130 when pulled down.

[0087] The technical solution provided in this embodiment uses a resistor as the potential pull-down unit 150, which is simple and inexpensive.

[0088] In some embodiments, refer to Figure 3 or Figure 4 The potential pull-up unit 140 includes a second resistor R2, one end of which is connected to the interrupt pin PIN_A, and the other end of which is connected to the power supply pin VCC.

[0089] Specifically, the potential pull-up unit 140 can be composed of a second resistor R2, one end of which is connected to the interrupt pin PIN_A, and the other end of which is connected to the power supply pin VCC.

[0090] When the external power supply 200 is connected, the pull-down unit 150 and the second resistor R2 form a voltage divider circuit. The resistance value of the second resistor R2 can be set by those skilled in the art according to the actual situation, as long as it can ensure that the potential of the interrupt pin PIN_A is higher than the logic high level threshold of the main control chip 130 when pulled up.

[0091] The technical solution provided in this embodiment uses a resistor as the potential pull-up unit 140, which is simple and inexpensive.

[0092] In some embodiments, the potential pull-up unit 140 is integrated within the main control chip 130, serving as a programmable weak pull-up resistor built into the interrupt pin PIN_A of the main control chip 130. The technical solution provided by this embodiment further reduces the number of components in the wake-up circuit 100, further lowers material costs, and saves printed circuit board space.

[0093] In some embodiments, the external power supply interface 110 is a universal serial bus interface.

[0094] Specifically, the external power supply interface 110 can be a Universal Serial Bus (USB) interface, including but not limited to USB Type-A, Micro-USB, and USB Type-C interfaces. Correspondingly, the external power supply 200 connected to the external power supply interface 110 is a USB power supply. When using a Universal Serial Bus interface, the power supply pin of the Universal Serial Bus interface corresponds to the positive terminal of the external power supply interface 110, and the ground pin GND of the Universal Serial Bus interface corresponds to the negative terminal of the external power supply interface 110.

[0095] This application also provides an electronic device, as described in the embodiments. Figure 5 The electronic device 400 includes a wake-up circuit 100 as described in any of the above embodiments and an internal power supply 300, the internal power supply 300 being connected to the internal power supply interface 120 in the wake-up circuit 100.

[0096] Specifically, the electronic device 400 can be a portable electronic device, such as a smartwatch, smart glasses, or other smart wearable devices, or a personal care appliance such as an electric shaver or electric hair dryer. The electronic device 400 includes an internal power supply 300 disposed within the device, which provides power to the device. The internal power supply 300 can specifically be a rechargeable battery such as a lithium-ion battery (Li-ion) or a lithium polymer battery (Li-Po) within the device 400.

[0097] In this embodiment, when the electronic device 400 is not connected to the external power supply 200, that is, when the external power supply interface 110 of the wake-up circuit 100 in the electronic device 400 is not connected to the external power supply 200, the internal power supply interface 120 of the internal power supply 300 supplies power to the main control chip 130 in the wake-up circuit 100 to maintain the normal operation of the main control chip 130. Simultaneously, when the electronic device 400 is connected to the external power supply 200, that is, when the external power supply interface 110 of the wake-up circuit 100 in the electronic device 400 is connected to the external power supply 200, the external power supply can charge the energy storage element through the wake-up circuit 100.

[0098] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0099] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above 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.

[0100] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A wake-up circuit, characterized by, include: External power supply interface; Internal power supply interface; The main control chip includes an interrupt pin, a power supply pin, and a ground pin; the power supply pin is connected to the positive terminal of the internal power supply interface, and the power supply pin is also used to connect to the positive terminal of the external power supply interface; the ground pin is connected to the negative terminal of the internal power supply interface. A potential pull-up unit, one end of which is connected to the interrupt pin and the other end of which is connected to the power supply pin; A pull-down unit is provided, one end of which is connected to the negative terminal of the external power supply interface, and the other end of which is connected to the interrupt pin; the main control chip is woken up when the potential of the interrupt pin changes.

2. The wake-up circuit of claim 1, wherein, The wake-up circuit further includes a switching unit, and the main control chip further includes a control pin. The first end of the switching unit is connected to the negative terminal of the external power supply interface and the potential pull-down unit, respectively. The second end of the switching unit is connected to the negative terminal of the internal power supply interface and the ground pin, respectively. The control end of the switching unit is connected to the control pin. The main control chip outputs a control signal to the switching unit through the control pin to control the conduction state of the switching unit.

3. The wake-up circuit of claim 2, wherein, The switching unit includes a first switching transistor, the first terminal of which is connected to the negative terminal of the external power supply interface and the pull-down unit, the second terminal of which is connected to the negative terminal of the internal power supply interface and the ground pin, and the control terminal of which is connected to the control pin.

4. The wake-up circuit of claim 3, wherein, The first switching transistor is an N-type insulated-gate field-effect transistor or a P-type insulated-gate field-effect transistor.

5. The wake-up circuit of claim 2, wherein, The control pins include a first control pin and a second control pin. The switching unit includes a second switching transistor and a third switching transistor. The first terminal of the second switching transistor is connected to the negative terminal of the external power supply interface and the potential pull-down unit, respectively. The second terminal of the second switching transistor is connected to the second terminal of the third switching transistor. The first terminal of the third switching transistor is connected to the negative terminal of the internal power supply interface and the ground pin, respectively. The control terminal of the second switching transistor is connected to the first control pin, and the control terminal of the third switching transistor is connected to the second control pin.

6. The wake-up circuit of claim 5, wherein, Both the second and third switching transistors are field-effect transistors, and the body diodes of the second and third switching transistors have opposite conduction directions.

7. The wake-up circuit of claim 1, wherein, The potential pull-down unit includes a first resistor, one end of which is connected to the negative terminal of the external power supply interface, and the other end of which is connected to the interrupt pin.

8. The wake-up circuit of claim 1, wherein, The potential pull-up unit includes a second resistor, one end of which is connected to the interrupt pin, and the other end of which is connected to the power supply pin.

9. The wake-up circuit according to any one of claims 1 to 8, characterized in that, The external power supply interface is a universal serial bus interface.

10. An electronic device, comprising: It includes an internal power supply and a wake-up circuit according to any one of claims 1-9, wherein the internal power supply is connected to the internal power supply interface.

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