CN217769523U

CN217769523U - Power management circuit applied to battery power supply equipment

Info

Publication number: CN217769523U
Application number: CN202220842337.7U
Authority: CN
Inventors: 李小舟; 李万宝; 宋真子; 王军; 章威
Original assignee: CETHIK Group Ltd
Current assignee: CETHIK Group Ltd
Priority date: 2022-04-12
Filing date: 2022-04-12
Publication date: 2022-11-08
Anticipated expiration: 2032-04-12

Abstract

The utility model discloses a be applied to battery power supply unit's power management circuit, battery power supply unit have main control chip and linear voltage regulator chip, and the power management circuit who is applied to battery power supply unit includes on-off control circuit and battery voltage detection circuitry. The circuit can provide a high-efficiency and flexible power supply control means for the electronic equipment, and power supply control of the equipment is realized through various modes under different use scenes in the modes of keys, a master control chip, an external USB (universal serial bus) line and the like. The battery power is detected through the main control chip, and functions such as power display, charging state display and low power protection are provided for the portable device. The circuit can protect the battery, avoid over-discharge, reduce the power consumption of the equipment and prolong the service life of the equipment.

Description

Power management circuit applied to battery power supply equipment

Technical Field

The utility model belongs to the technical field of the battery powered technology, concretely relates to be applied to battery power supply unit's power management circuit.

Background

With the development of science and technology, portable intelligent electronic devices have been widely demanded and applied in various fields. Such devices typically require power from rechargeable batteries to improve the portability and mobility of the device. Currently, for battery powered devices, the management of power supply is usually implemented by a dedicated battery management chip. Regardless of whether the device is in a power-on or power-off state, the battery management chip needs to maintain a power supply state to ensure that the device can be powered on at any time when needed, which may bring extra power consumption and cost, and meanwhile, continuous work may cause excessive discharge of the battery, which affects the service life of the battery.

In the prior art, for example, patent document with patent publication number CN201922165957.2, a power management circuit applied to an intelligent terminal is provided, which can detect the electric quantity of a power supply of the intelligent terminal, control the intelligent terminal to be powered on and powered off according to the power supply requirement required by the intelligent terminal to work, and ensure the power supply stability of the power supply of the intelligent terminal. The circuit can realize the control function only by keeping the power supply of the control chip in the on-off state.

In the prior art, for example, patent document No. CN201880001255.6 provides a power management circuit, which can implement on/off management of a battery power supply device, so that the battery does not supply power to an on/off management module any more in a power-off state, thereby reducing power consumption of the battery. The technology does not need to keep the chip powered to control the switch, but needs to realize the function of controlling the connection and disconnection of the battery by adding a protection board at the core of the battery.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a be applied to battery powered equipment's power management circuit, this circuit can protect the battery, avoids overdischarge, reduces the equipment consumption, prolongs the life of equipment.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

a power management circuit applied to a battery-powered device, the battery-powered device is provided with a main control chip and a linear voltage stabilizer chip, the power management circuit applied to the battery-powered device comprises a switch control circuit and a battery voltage detection circuit, wherein:

the switch control circuit comprises three branches connected with the linear voltage stabilizer chip, wherein the first branch comprises a resistor R3, a resistor R4, a resistor R5 and a diode D2, the cathode of the diode D2 is connected with the enabling end of the linear voltage stabilizer chip, the anode of the diode D2 is connected with one end of the resistor R5, the other end of the resistor R5 is respectively connected with one ends of the resistor R3 and the resistor R4, the other end of the resistor R4 is grounded, and the other end of the resistor R3 is connected with a USB line interface;

the second branch circuit comprises a resistor R1, a capacitor C1, a key K1, a voltage stabilizing diode D1, a resistor R2, a resistor R6 and a diode D3, wherein the cathode of the diode D3 is connected with the enabling end of the linear voltage stabilizer chip, the anode of the diode D3 is connected with one end of the resistor R6, the other end of the resistor R6 is respectively connected with one ends of the key K1, the voltage stabilizing diode D1 and the resistor R2, the other end of the resistor R6 is simultaneously used as a SWITCH pin to be connected to a GPIO pin of the main control chip, the other end of the resistor R2 is grounded, the other end of the voltage stabilizing diode D1 is grounded, the other end of the key K1 is respectively connected with one ends of the resistor R1 and the capacitor C1, the other end of the capacitor C1 is grounded, and the other end of the resistor R1 is connected with a high level;

and the third branch circuit comprises a resistor R7 and a diode D4, the cathode of the diode D4 is connected with the enabling end of the linear voltage regulator chip, the anode of the diode D4 is connected with one end of the resistor R7, and the other end of the resistor R7 is connected to a GPIO pin of the main control chip as a LOW _ PWR pin.

Several alternatives are provided below, but not as an additional limitation to the above general solution, but merely as a further addition or preference, each alternative being combinable individually for the above general solution or among several alternatives without technical or logical contradictions.

Preferably, a resistor R8 is connected to an enable end of the linear regulator chip, and the other end of the resistor R8 is grounded.

Preferably, the battery voltage detection circuit comprises a resistor R9, a resistor R10, a resistor R11, a resistor R12, a resistor R13, a resistor R14, a capacitor C2, a capacitor C3, a MOS tube Q1 and a MOS tube Q2;

one end of a resistor R10 is grounded, the other end of the resistor R10 is connected with a resistor R9 and a capacitor C2 respectively, the other end of the resistor R10 is connected with an ADC (analog-to-digital converter) pin of the main control chip as a VBAT _ DETECT pin at the same time, the other end of the capacitor C2 is grounded, the other end of the resistor R9 is connected with a drain electrode of the MOS tube Q2, a source electrode of the MOS tube Q2 is connected with a high level, a resistor R11 is connected between a grid electrode and a source electrode of the MOS tube Q2, one end of a resistor R12 is connected with the grid electrode of the MOS tube Q2, the other end of the resistor R12 is connected with a drain electrode of the MOS tube Q1, the source electrode of the MOS tube Q1 is grounded, the grid electrode of the MOS tube Q1 is connected with one ends of a resistor R13, a resistor R14 and a capacitor C3 respectively, the other end of the resistor R14 is grounded, and the other end of the resistor R13 is connected with a GPIO pin of the main control chip as a VBAT _ DETECT pin.

Preferably, the MOS transistor Q1 is an N-type bias MOS transistor, and the MOS transistor Q2 is a P-type bias MOS transistor.

The utility model provides a be applied to battery power supply unit's power management circuit mainly is applied to battery powered's portable intelligent electronic equipment. The circuit can provide a high-efficiency and flexible power supply control means for the electronic equipment, and power supply control of the equipment is realized through various modes under different use scenes through modes such as keys, a master control chip, an external USB line and the like. The battery power is detected through the main control chip, and functions such as power display, charging state display and low power protection are provided for the portable device. The circuit can protect the battery, avoid over-discharge, reduce the power consumption of the equipment and prolong the service life of the equipment. Compared with the design with similar functions, the circuit has lower realization difficulty, smaller volume and lower cost.

Drawings

Fig. 1 is a structural diagram of a power management circuit applied to a battery-powered device of the present invention;

fig. 2 is a schematic circuit diagram of the switching control circuit of the present invention;

fig. 3 is a schematic circuit diagram of the battery voltage detection circuit of the present invention;

fig. 4 is a schematic diagram of the power management circuit applied to the battery-powered device of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

It will be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. Unless defined otherwise, 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 invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

The embodiment provides a power management circuit applied to battery power supply equipment, which can control the power on and off of the battery power supply equipment through a touch switch and can monitor and calculate the electric quantity of a battery in real time. When the main control chip detects that the electric quantity is low or the equipment does not work for a long time and the like, the main control chip directly cuts off the power supply of the equipment.

In addition, when the battery power supply equipment is shut down, the main control chip can be awakened by inserting the USB line. The on-off of the battery power supply equipment can be controlled in multiple modes according to the use scene of the battery power supply equipment, and the power supply does not need to be kept by an independent power management chip after the battery power supply equipment is turned off, so that the power consumption can be reduced, and the service life of the battery can be prolonged.

As shown in fig. 1, the power management circuit of the present embodiment is mainly composed of two parts, one part is a switch control circuit, and the other part is a battery voltage detection circuit, and the two parts are matched to perform the management function of each function of the power supply. The battery power supply equipment is provided with a main control chip and a linear voltage stabilizer chip, the linear voltage stabilizer chip outputs 3.3V (namely VCC3V3 in figure 1) to the main control chip, and a battery voltage detection circuit and a switch control circuit are used at the periphery of the main control chip and the linear voltage stabilizer chip to complete reasonable power supply management.

As shown in fig. 2, the switch control circuit of this embodiment includes three branches connected to the linear regulator chip, that is, a first branch, a second branch, and a third branch.

The first branch circuit comprises a resistor R3, a resistor R4, a resistor R5 and a diode D2, the cathode of the diode D2 is connected with an enabling end PWR _ EN of the linear voltage stabilizer chip, the anode of the diode D2 is connected with one end of the resistor R5, the other end of the resistor R5 is connected with one ends of the resistor R3 and the resistor R4 respectively, the other end of the resistor R4 is grounded, and the other end of the resistor R3 is connected with a USB line interface.

The second branch circuit comprises a resistor R1, a capacitor C1, a key K1, a voltage stabilizing diode D1, a resistor R2, a resistor R6 and a diode D3, wherein the cathode of the diode D3 is connected with an enable end PWR _ EN of the linear voltage stabilizer chip, the anode of the diode D3 is connected with one end of the resistor R6, the other end of the resistor R6 is respectively connected with one ends of the key K1, the voltage stabilizing diode D1 and the resistor R2, the other end of the resistor R6 is simultaneously used as a SWITCH pin to be connected to a GPIO pin of the main control chip, the other end of the resistor R2 is grounded, the other end of the voltage stabilizing diode D1 is grounded, the other end of the key K1 is respectively connected with one ends of the resistor R1 and the capacitor C1, the other end of the capacitor C1 is grounded, the other end of the resistor R1 is connected with a high level, and the high level can be led out from a battery power supply interface VBAT.

The third branch circuit comprises a resistor R7 and a diode D4, the cathode of the diode D4 is connected with the enable end PWR _ EN of the linear voltage regulator chip, the anode of the diode D4 is connected with one end of the resistor R7, and the other end of the resistor R7 is connected to the GPIO pin of the main control chip as a LOW _ PWR pin. The enable terminal PWR _ EN of the linear voltage stabilizer chip is connected with a resistor R8, and the other end of the resistor R8 is grounded.

In the SWITCH control circuit in this embodiment, VBUS is a USB cable interface, VBAT is a battery power supply interface, a SWITCH pin and a LOW _ PWR pin are connected to the main control chip, the SWITCH pin is used to detect a key state, and the LOW _ PWR is used to control the linear regulator chip. Resistors R1, R2, R3, and R4 are used for voltage division, R5, R6, and R7 are used for current limiting, and R8 is used for turning off the linear regulator in a default state. The voltage stabilizing diode D1 is used for stabilizing the voltage input to the main control chip within a certain range, and the diodes D2, D3 and D4 are used for preventing the current from flowing back to the main control chip. The PWR _ EN pin is connected with an enabling end of the linear voltage stabilizer chip to control the work of the linear voltage stabilizer. Three branches are connected to the PWR _ EN pin, which represents the three methods for pulling the enable pin of the linear regulator high.

In another embodiment, taking the main control chip STM32L151RD as an example, the SWITCH pin is connected to the GPIO pin PC10 of the main control chip, and the LOW _ PWR pin is connected to the GPIO pin PD2 of the main control chip.

As shown in fig. 3, the battery voltage detection circuit of the present embodiment includes a resistor R9, a resistor R10, a resistor R11, a resistor R12, a resistor R13, a resistor R14, a capacitor C2, a capacitor C3, a MOS transistor Q1, and a MOS transistor Q2.

One end of a resistor R10 is grounded, the other end of the resistor R10 is respectively connected with a resistor R9 and a capacitor C2, the other end of the resistor R10 is simultaneously used as a VBAT _ DETECT pin to be connected with an ADC pin of a main control chip, the other end of the capacitor C2 is grounded, the other end of the resistor R9 is connected with a drain electrode of an MOS tube Q2, a source electrode of the MOS tube Q2 is connected with a high level, a resistor R11 is connected between a grid electrode and a source electrode of the MOS tube Q2, one end of a resistor R12 is connected with the grid electrode of the MOS tube Q2, the other end of the resistor R12 is connected with a drain electrode of the MOS tube Q1, the source electrode of the MOS tube Q1 is grounded, the grid electrode of the MOS tube Q1 is respectively connected with one ends of a resistor R13, a resistor R14 and a capacitor C3, the other end of the resistor R14 is grounded, and the other end of the resistor R13 is used as a VBAT _ EN pin to be connected with a pin of the main control chip.

The MOS tube Q1 is an N-type bias MOS tube, and the MOS tube Q2 is a P-type bias MOS tube.

In the battery voltage detection circuit of this embodiment, VBAT _ EN is an electric quantity detection enable pin connected to a GPIO interface of the main control chip, and VBAT _ DETECT is an electric quantity detection pin connected to an ADC pin of the main control chip. The resistors R9-R14 in the figure all function as voltage division, so that the MOS tube can work at a proper voltage, and the voltage and the current of the VBAT _ DETECT pin are kept within a certain range. When the electric quantity detection is not needed, Q2 and Q3 are closed, and a circuit between VBAT and the ground is not conducted, so that the battery is prevented from consuming electric energy through the voltage detection circuit. When the electric quantity needs to be detected, the VBAT _ EN pin is pulled high by the main control chip, so that the Q2 and the Q3 are conducted, and the voltage of the battery can be measured through the ADC of the main control chip. The circuit can be used for displaying the electric quantity of the battery, protecting the low electric quantity and the like. The cooperation switch control circuit can be when battery electric quantity is lower, by the initiative outage of master control chip to avoid the overdischarge of battery.

IN another embodiment, taking the main control chip STM32L151RD as an example, the VBAT _ DETECT pin is connected to the ADC pin ADC _ IN10 of the main control chip, and the VBAT _ EN pin is connected to the GPIO pin PC11 of the main control chip.

As shown in fig. 4, the working principle of the power management circuit provided by this embodiment is as follows:

the linear voltage stabilizer chip with the enabling function provides power for the battery power supply equipment, when the enabling pin inputs a high level, the whole battery power supply equipment is powered on, when the enabling pin inputs a low level, the linear voltage stabilizer chip does not work, and the whole battery power supply equipment is powered off.

The high level can be provided for the enable pin of the linear voltage regulator chip through three ways: the soft touch key K1 is switched on to connect the enable pin to a high level, a USB line is connected to provide the high level for the enable pin, and the main control chip directly outputs the high level for the enable pin under the working condition.

It should be noted that the linear regulator chip and the main control chip mentioned herein may be a regulator chip and a main control chip used by the battery powered device itself, the regulator chip has an enabling function, and the main control chip can control the pin to output a high level, without additionally introducing a special chip to the present circuit. Of course, the linear voltage regulator chip and the main control chip may also be external components of the battery power supply device, so as to meet the requirement of butt joint with the power management circuit of the embodiment.

Therefore, when the battery power supply equipment is in a shutdown state, the key K1 is pressed for a long time, the circuit can be switched on to provide high level for the enabling pin of the linear voltage stabilizer chip, and the main control chip is started. Because the key K1 cannot keep the high level continuously after being released, after the main control chip is powered on and started, the main control chip keeps outputting the high level to keep the linear voltage regulator to continuously work, and the key K1 can be released at the moment. When the power-on is charged, the main control chip and the linear voltage stabilizer chip keep working.

Under battery powered equipment shutdown state, when inserting the USB charging wire through USB line interface, can directly provide the high level for linear voltage regulator chip's messenger pin through the USB line, main control chip and linear voltage regulator chip keep work, for the equipment power supply.

When the battery power supply equipment needs to be shut down in a starting state, the key K1 is pressed for a long time, the main control chip stops providing high level for the enabling pin of the linear voltage stabilizer after detecting a switching signal, the chip of the linear voltage stabilizer stops working after the key K1 is released, and the battery power supply equipment is powered off.

When the main control chip detects that the battery is low in power (for example, the battery power is only 10% of full power), or the battery power supply device is not used for a long time in a power-on state, or other conditions that the battery power supply device needs to be powered off are detected, the main control chip can directly pull down the enable pin of the linear voltage regulator, the linear voltage regulator can be directly powered off under the condition that the tact switch is not pressed, and the high level is not provided for the enable pin of the linear voltage regulator chip through the USB wire in the state.

It should be noted that there are many methods for determining that the battery powered device is not used for a long time in the power-on state according to different devices. For example, it may be determined that the bluetooth chip of the device has not performed data transmission for a long time, or that the IMU (inertial measurement unit) has not detected movement of the device for a long time, or the like. The main control chip may perform the determination according to the obtained information, and the present embodiment is not limited thereto.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-described embodiments only represent some embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. The utility model provides a be applied to battery powered equipment's power management circuit, battery powered equipment has main control chip and linear voltage regulator chip, its characterized in that, be applied to battery powered equipment's power management circuit, including on-off control circuit and battery voltage detection circuit, wherein:

the third branch circuit comprises a resistor R7 and a diode D4, the cathode of the diode D4 is connected with the enabling end of the linear voltage regulator chip, the anode of the diode D4 is connected with one end of the resistor R7, and the other end of the resistor R7 is used as a LOW _ PWR pin and is connected to a GPIO pin of the main control chip.

2. The power management circuit as claimed in claim 1, wherein the resistor R8 is connected to the enable terminal of the linear regulator chip, and the other terminal of the resistor R8 is grounded.

3. The power management circuit applied to the battery-powered device according to claim 1, wherein the battery voltage detection circuit comprises a resistor R9, a resistor R10, a resistor R11, a resistor R12, a resistor R13, a resistor R14, a capacitor C2, a capacitor C3, a MOS transistor Q1, a MOS transistor Q2;

4. The power management circuit as claimed in claim 3, wherein the MOS transistor Q1 is an N-type biased MOS transistor, and the MOS transistor Q2 is a P-type biased MOS transistor.