Self-holding power switch circuit suitable for low-power-consumption electronic equipment

Abstract

The utility model discloses a self-hold power switch circuit suitable for low power consumption electronic equipment, the whole circuit is divided into a power supply control MOS circuit, a self-hold circuit, a button power-on circuit, a button detection circuit and the like, the power supply control MOS circuit mainly controls the communication switch function of a battery power supply and a system power supply, and when power needs to be supplied to a system, the self-hold circuit is connected with the button power-on circuit and the button detection circuit. The MOS tube Q21 is opened through the self-holding circuit or the key power-on circuit to provide power for the system, and when the system does not need power supply, namely shutdown is needed, the MOS tube Q21 is closed through the self-holding circuit or the key detection circuit to disconnect a power supply path from a battery to the system. Therefore, battery consumption is reduced to the utmost extent, and gradual consumption of battery power during transportation or when a device is not used during shutdown is avoided.

Description

Technical Field

[0001] The utility model belongs to the technical field of low-power switch, and in particular relates to a self-holding power switch circuit suitable for low-power electronic equipment. Background Art

[0002] At present, the switch commonly used in low-power electronic devices is a dip switch, but the dip switch generally requires the user to turn it on and off to physically realize the circuit, which is not a good user experience; and the dip switch cannot realize the system's autonomous power-off, and the user must manually turn off the power. In addition, the dip switch is generally large in size and rough in appearance, which is not suitable for wearable devices or other miniaturized low-power devices. Therefore, it is urgent to develop a miniaturized self-holding power switch circuit suitable for low-power electronic devices. Utility Model Content

[0003] The utility model aims to solve the problems of the prior art and provides a self-holding power switch circuit suitable for low-power electronic equipment.

[0004] In order to solve the technical problem, the technical solution of the utility model is: a self-holding power switch circuit suitable for low-power electronic equipment, including a power control MOS circuit, a self-holding circuit, a key power-on circuit and a key detection circuit, the power control MOS circuit includes a MOS tube Q21 and a pull-up resistor R139, one end of the pull-up resistor R139 is connected to the G pole of the MOS tube Q21, the S pole of the MOS tube Q21 and the other end of the pull-up resistor R139 are respectively connected to VBAT_IN, VBAT_IN comes from a 1S lithium battery, and the D pole of the MOS tube Q21 is connected to VBAT to power the system; the self-holding circuit includes a MOS tube Q22, the G pole of the MOS tube Q22 is connected to POWHOLD_MCU, and POWHOLD_MCU is connected to the IO pin of the single-chip microcomputer. pin, the D pole of the MOS tube Q22 is connected to the G pole of the MOS tube Q21, the S pole of the MOS tube Q22 is grounded, and the G pole and the D pole of the MOS tube Q22 are also connected to VBUS_5V; the key power-on circuit includes a key K4 and a transistor Q23, one end of the key K4 is respectively connected to VBAT_IN and ground, the other end of the key K4 is connected to the B pole of the transistor Q23, the C pole of the transistor Q23 is connected to the G pole of the MOS tube Q21, and the E pole of the transistor Q23 is grounded; the key detection circuit includes a transistor Q24, the B pole of the transistor Q24 is connected to the key K4, the C pole of the transistor Q24 is connected to POWKEY_MCU, POWKEY_MCU is connected to the IO input of the MCU, the C pole of the transistor Q24 is also connected to 1V8, and the E pole of the transistor Q24 is grounded.

[0005] Preferably, the power control MOS circuit also includes capacitor C104, capacitor C105, capacitor C106, capacitor C107 and capacitor C109, one end of capacitor C104 and capacitor C109 are respectively connected to VBAT_IN, the other ends of capacitor C104 and capacitor C109 are respectively grounded, one end of capacitor C105 is respectively connected to one end of pull-up resistor R139 and the S pole of MOS tube Q21, the other end of capacitor C105 is respectively connected to the other end of pull-up resistor R139 and the G pole of MOS tube Q21, one end of capacitor C106 and capacitor C107 are respectively connected to VBAT, and the other ends of capacitor C106 and capacitor C107 are respectively grounded.

[0006] Preferably, the MOS tube Q21 is an AO3415A model PMOS tube.

[0007] Preferably, the self-holding circuit also includes a resistor R140, a resistor R141 and a resistor R161, the G pole of the MOS tube Q22 is connected to POWHOLD_MCU through the resistor R140, the G pole of the MOS tube Q22 is connected to VBUS_5V through the resistor R161, VBUS_5V is connected to a 5V charger, and the S pole of the MOS tube Q22 is respectively connected to the resistor R140 and the resistor R161 through the resistor R141.

[0008] Preferably, the MOS transistor Q22 is an N-channel MOS transistor.

[0009] Preferably, the button power-on circuit also includes resistor R92, resistor R142, resistor R143, resistor R145 and capacitor C81, the B pole of the transistor Q23 is connected to the button K4 through the resistor R142, the button K4 is connected to BAT_IN through the resistor R92, the button K4 is grounded through the resistor R145, one end of the capacitor C81 is respectively connected to the button K4 and the resistor R142, the other end of the capacitor C81 is grounded, and the E pole of the transistor Q23 is also connected to the resistor R142 through the resistor R143.

[0010] Preferably, the transistor Q23 is an NPN transistor.

[0011] Preferably, the key detection circuit also includes resistors R146, R147 and R148, the B pole of transistor Q24 is connected to key K4 through resistor R146, the E pole of transistor Q24 is connected to resistor R146 through resistor R147, and the C pole of transistor Q24 is connected to 1V8 through resistor R148.

[0012] Compared with the prior art, the advantages of the utility model are:

[0013] (1) The utility model discloses a self-holding power switch circuit suitable for low-power electronic equipment. The whole circuit is divided into several parts, such as a power control MOS circuit, a self-holding circuit, a key power-on circuit, and a key detection circuit. The power control MOS circuit mainly controls the switching function of the battery power supply and the system power supply. When the system needs to be powered, the MOS tube Q21 is turned on through the self-holding circuit or the key power-on circuit to provide power to the system. When the system does not need to be powered, that is, it needs to be shut down, the MOS tube Q21 is turned off through the self-holding circuit or the key detection circuit to disconnect the power supply path from the battery to the system. The utility model can realize the automatic control of the power supply of the device itself and realize the automatic power off at the end of work, thereby greatly reducing the battery consumption and avoiding the gradual consumption of the battery power during transportation or when the device is turned off and not in use;

[0014] (2) The switch circuit of the utility model has extremely low power consumption. When used as a low-power switch, it will not increase the power consumption of the low-power device itself. The cost of the switch circuit is extremely low. Only a few transistors and MOS tubes are used to realize all key-press power-on, self-holding, automatic power-off and other functions;

[0015] (3) The switch circuit of the utility model has a small size, extremely low power consumption, low cost, and can realize the device to automatically shut down the power supply, thereby achieving an extremely low power consumption switch circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 , a circuit schematic diagram of a self-holding power switch circuit suitable for low-power electronic equipment of the utility model;

[0017] Figure 2 , the utility model is a working flow chart of a self-holding power switch circuit suitable for low-power electronic equipment. DETAILED DESCRIPTION

[0018] The following describes the specific implementation of the utility model in conjunction with embodiments:

[0019] It should be noted that the structures, proportions, sizes, etc. shown in this specification are only used to match the contents disclosed in the specification so that people familiar with this technology can understand and read them, and are not used to limit the conditions under which the present invention can be implemented. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0020] Example 1

[0021] like Figure 1As shown, the utility model discloses a self-holding power switch circuit suitable for low-power electronic equipment, including a power control MOS circuit, a self-holding circuit, a key power-on circuit and a key detection circuit. The power control MOS circuit includes a MOS tube Q21 and a pull-up resistor R139, one end of the pull-up resistor R139 is connected to the G pole of the MOS tube Q21, the S pole of the MOS tube Q21 and the other end of the pull-up resistor R139 are respectively connected to VBAT_IN, VBAT_IN comes from a 1S lithium battery, and the D pole of the MOS tube Q21 is connected to VBAT to power the system; the self-holding circuit includes a MOS tube Q22, the G pole of the MOS tube Q22 is connected to POWHOLD_MCU, POWHOLD_MCU is connected to the IO pin of the single-chip microcomputer, and the MOS tube Q22 is connected to the G pole of the MOS tube Q21. The D pole of the transistor Q22 is connected to the G pole of the MOS tube Q21, the S pole of the MOS tube Q22 is grounded, and the G pole and the D pole of the MOS tube Q22 are also connected to VBUS_5V; the key power-on circuit includes a key K4 and a transistor Q23, one end of the key K4 is respectively connected to VBAT_IN and the ground, the other end of the key K4 is connected to the B pole of the transistor Q23, the C pole of the transistor Q23 is connected to the G pole of the MOS tube Q21, and the E pole of the transistor Q23 is grounded; the key detection circuit includes a transistor Q24, the B pole of the transistor Q24 is connected to the key K4, the C pole of the transistor Q24 is connected to POWKEY_MCU, POWKEY_MCU is connected to the IO input of the MCU, the C pole of the transistor Q24 is also connected to 1V8, and the E pole of the transistor Q24 is grounded.

[0022] Example 2

[0023] like Figure 1 As shown, preferably, the power control MOS circuit also includes capacitor C104, capacitor C105, capacitor C106, capacitor C107 and capacitor C109, one end of capacitor C104 and capacitor C109 are respectively connected to VBAT_IN, the other ends of capacitor C104 and capacitor C109 are respectively grounded, one end of capacitor C105 is respectively connected to one end of pull-up resistor R139 and the S pole of MOS tube Q21, the other end of capacitor C105 is respectively connected to the other end of pull-up resistor R139 and the G pole of MOS tube Q21, one end of capacitor C106 and capacitor C107 are respectively connected to VBAT, and the other ends of capacitor C106 and capacitor C107 are respectively grounded.

[0024] Preferably, the MOS tube Q21 is an AO3415A model PMOS tube.

[0025] In the power control MOS circuit, the left-side network VBAT_IN of the circuit comes from a 1S lithium battery, and the right-side network VBAT supplies power to the system after passing through a low-power switch circuit. The MOS transistor Q21 is an AO3415A type PMOS transistor. In its default state, its G pole is pulled high to the VBAT_IN level by the pull-up resistor R139. At this time, Vgs > Vth (Vth is the switching threshold of the MOS transistor Q21), the MOS transistor Q21 is not conducting, and the VBAT power supply is turned off. When the G pole of the MOS transistor Q21 is pulled low by other control circuits, Vgs < Vth, the MOS transistor Q21 is turned on, the VBAT power supply is turned on, and the system starts. Therefore, only by controlling the G pole of the MOS transistor Q21 in the power control circuit by other module circuits can the power supply be turned on and off.

[0026] Embodiment 3

[0027] As Figure 1 shown, preferably, the self-holding circuit further includes a resistor R140, a resistor R141, and a resistor R161. The G pole of the MOS transistor Q22 is connected to the POWHOLD_MCU through the resistor R140, the G pole of the MOS transistor Q22 is connected to the VBUS_5V through the resistor R161, the VBUS_5V is connected to a 5V charger, and the S pole of the MOS transistor Q22 is connected to the resistor R140 and the resistor R161 respectively through the resistor R141.

[0028] Preferably, the MOS transistor Q22 is an N-channel MOS transistor.

[0029] The self-holding circuit is an important part of the entire low-power switch circuit. The left-side network POWHOLD_MCU of the circuit is connected to the IO pin of the single-chip microcomputer. When the circuit needs to be self-held in the power-on stage, the MCU provides an IO high level to supply power to the G pole of the MOS transistor Q22 (AO3416) here. AO3416 is an N-channel MOS transistor. When the voltage of the G pole is higher than the voltage of the S pole and Vgs > Vth, the MOS transistor Q22 conducts. At this time, the MOS transistor Q22 conducts and pulls the G pole of the MOS transistor Q21 low, so that the MOS transistor Q21 conducts, turns on the power control circuit, and VBAT maintains power supply.

[0030] Embodiment 4

[0031] As Figure 1As shown, preferably, the button power-on circuit also includes resistor R92, resistor R142, resistor R143, resistor R145 and capacitor C81, the B pole of the transistor Q23 is connected to the button K4 through the resistor R142, the button K4 is connected to BAT_IN through the resistor R92, the button K4 is grounded through the resistor R145, one end of the capacitor C81 is respectively connected to the button K4 and the resistor R142, the other end of the capacitor C81 is grounded, and the E pole of the transistor Q23 is also connected to the resistor R142 through the resistor R143.

[0032] Preferably, the transistor Q23 is an NPN transistor.

[0033] Preferably, the key detection circuit also includes resistors R146, R147 and R148, the B pole of transistor Q24 is connected to key K4 through resistor R146, the E pole of transistor Q24 is connected to resistor R146 through resistor R147, and the C pole of transistor Q24 is connected to 1V8 through resistor R148.

[0034] The key power-on circuit and the key detection circuit are combined together. The function of the key power-on circuit is that when power-on is required, the user presses the key K4, and the VBAT_IN voltage is transmitted to the B level of the transistor Q23 through the key K4. The transistor Q23 is an NPN transistor. When the B level is high, its CE is turned on. This circuit connects the C level of the transistor to the G pole of the MOS tube Q21 of the power control MOS circuit. Therefore, the power control MOS circuit can also be turned on at this time, and VBAT is powered on to power the system. The key detection circuit is designed for users to manually shut down. If the user needs to manually shut down the device, long press the key K4. At this time, the B level of the transistor Q24 of the key detection circuit is high, and the transistor Q24 is turned on, thereby pulling the network POWKEY_MCU / down. Its working principle is consistent with the key power-on circuit. The network POWKEY_MCU / is connected to the IO input port of the MCU. When the MCU detects that the key is pressed for a long time, it starts the power-off process and pulls the MCU output IO port POWHOLD_MCU low. The corresponding self-holding circuit is powered off, so that the power control circuit is powered off and the system is powered off and shut down.

[0035] The working principle of the utility model is as follows:

[0036] like Figure 1As shown, the utility model discloses a self-holding power switch circuit suitable for low-power electronic equipment. The whole circuit is divided into several parts, such as a power control MOS circuit, a self-holding circuit, a key power-on circuit, and a key detection circuit. The power control MOS circuit mainly controls the connecting switch function of the battery power supply and the system power supply. When the system needs to be powered, the MOS tube Q21 is turned on by the self-holding circuit or the key power-on circuit to provide power for the system. When the system does not need to be powered, that is, it needs to be shut down, the MOS tube Q21 is turned off by the self-holding circuit or the key detection circuit to disconnect the power supply path from the battery to the system. The utility model can realize automatic control of the power supply of the device itself and automatically shut down the power supply at the end of work, thereby greatly reducing battery consumption and avoiding the gradual consumption of battery power during transportation or when the device is shut down and not in use.

[0037] The switch circuit of the utility model has extremely low power consumption itself, and its use as a low-power switch function will not increase the power consumption of the low-power device itself. The switch circuit cost is extremely low, and only a few transistors and MOS tubes are used to realize all key-press power-on, self-holding, automatic power-off and other functions.

[0038] The switch circuit of the utility model has a small size, extremely low power consumption, low cost, and can realize the device to automatically shut down the power supply, thereby realizing a switch circuit with extremely low power consumption.

[0039] The workflow of this utility model is as follows:

[0040] like Figure 2 As shown, in the system power-off state, the user presses the button (button K4) to start the system, temporarily power on the system, the MCU starts, the IO port POWHOLD_MCU is pulled high, the self-holding circuit keeps the system powered on, and the system works. When the power needs to be cut off, the MCU controls the system to end work or the user long presses the POW button (button K4), the MCU controls the IO port POWHOLD_MCU to be pulled low, the self-holding circuit is released, and the system powers off.

[0041] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of ordinary technicians in this field without departing from the purpose of the present invention.

[0042] Many other changes and modifications can be made without departing from the concept and scope of the utility model. It should be understood that the utility model is not limited to a specific embodiment, and the scope of the utility model is defined by the appended claims.

Claims

1. A self-holding power switch circuit suitable for low-power electronic equipment, characterized in that: The invention comprises a power control MOS circuit, a self-holding circuit, a key power-on circuit and a key detection circuit. The power control MOS circuit comprises a MOS tube Q21 and a pull-up resistor R139. One end of the pull-up resistor R139 is connected to the G pole of the MOS tube Q21. The S pole of the MOS tube Q21 and the other end of the pull-up resistor R139 are respectively connected to VBAT_IN. VBAT_IN comes from a 1S lithium battery. The D pole of the MOS tube Q21 is connected to VBAT to power the system. The self-holding circuit comprises a MOS tube Q22. The G pole of the MOS tube Q22 is connected to POWHOLD_MCU. POWHOLD_MCU is connected to the IO pin of the single-chip microcomputer. The D pole of the MOS tube Q22 is connected to the The G pole of the MOS tube Q21 is connected to the S pole of the MOS tube Q22, and the G pole and the D pole of the MOS tube Q22 are also connected to VBUS_5V; the key power-on circuit includes a key K4 and a transistor Q23, one end of the key K4 is respectively connected to VBAT_IN and ground, the other end of the key K4 is connected to the B pole of the transistor Q23, the C pole of the transistor Q23 is connected to the G pole of the MOS tube Q21, and the E pole of the transistor Q23 is grounded; the key detection circuit includes a transistor Q24, the B pole of the transistor Q24 is connected to the key K4, the C pole of the transistor Q24 is connected to POWKEY_MCU, POWKEY_MCU is connected to the IO input of the MCU, the C pole of the transistor Q24 is also connected to 1V8, and the E pole of the transistor Q24 is grounded.

2. A self-holding power switch circuit suitable for low-power electronic equipment according to claim 1, characterized in that: The power control MOS circuit also includes capacitor C104, capacitor C105, capacitor C106, capacitor C107 and capacitor C109, one end of capacitor C104 and capacitor C109 are respectively connected to VBAT_IN, the other ends of capacitor C104 and capacitor C109 are respectively grounded, one end of capacitor C105 is respectively connected to one end of pull-up resistor R139 and the S pole of MOS tube Q21, the other end of capacitor C105 is respectively connected to the other end of pull-up resistor R139 and the G pole of MOS tube Q21, one end of capacitor C106 and capacitor C107 are respectively connected to VBAT, and the other ends of capacitor C106 and capacitor C107 are respectively grounded.

3. A self-holding power switch circuit suitable for low-power electronic equipment according to claim 2, characterized in that: The MOS tube Q21 is a AO3415A model PMOS tube.

4. The self-holding power switch circuit suitable for low-power electronic equipment according to claim 1, characterized in that: The self-holding circuit also includes a resistor R140, a resistor R141 and a resistor R161. The G pole of the MOS tube Q22 is connected to POWHOLD_MCU through the resistor R140, the G pole of the MOS tube Q22 is connected to VBUS_5V through the resistor R161, VBUS_5V is connected to a 5V charger, and the S pole of the MOS tube Q22 is connected to the resistor R140 and the resistor R161 respectively through the resistor R141.

5. A self-holding power switch circuit suitable for low-power electronic equipment according to claim 4, characterized in that: The MOS transistor Q22 is an N-channel MOS transistor.

6. The self-holding power switch circuit suitable for low-power electronic equipment according to claim 1, characterized in that: The button power-on circuit also includes resistor R92, resistor R142, resistor R143, resistor R145 and capacitor C81. The B pole of the transistor Q23 is connected to the button K4 through the resistor R142. The button K4 is connected to BAT_IN through the resistor R92. The button K4 is grounded through the resistor R145. One end of the capacitor C81 is respectively connected to the button K4 and the resistor R142. The other end of the capacitor C81 is grounded. The E pole of the transistor Q23 is also connected to the resistor R142 through the resistor R143.

7. A self-holding power switch circuit suitable for low-power electronic equipment according to claim 6, characterized in that: The transistor Q23 is an NPN transistor.

8. The self-holding power switch circuit suitable for low-power electronic equipment according to claim 1, characterized in that: The key detection circuit also includes resistors R146, R147 and R148. The B pole of transistor Q24 is connected to key K4 through resistor R146, the E pole of transistor Q24 is connected to resistor R146 through resistor R147, and the C pole of transistor Q24 is connected to 1V8 through resistor R148.

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