WO2020047693A1 - Power supply management circuit - Google Patents

Abstract

A power supply management circuit, comprising a power on and off management module, a battery and a load switch, wherein a detection end of the power on and off management module is used for detecting a power on or power off signal, a first control end thereof is connected to the load switch and a second control end thereof is connected to a battery protection board; when the power off signal is detected, the turning-off of the load switch is controlled to stop supplying power to a load, and the battery protection board is controlled to cut off the output of electric energy from a battery; and when the power on signal is detected, the turning-on of the battery protection board is controlled, such that the battery continuously supplies power to the power on and off management module, and the turning-off of the load switch is controlled to supply power to the load. Further provided is another power supply management circuit, wherein a switch circuit is connected between a battery and a power on and off management module, and the energization between the battery and the power on and off management module is enabled or disabled by means of controlling the turning-on or turning-off of the switch circuit. The management of the power on and off of a battery power supplying device can be realized, such that a battery no longer supplies power to a power on and off management module in a power-off state, thereby reducing the power consumption of the battery.

Description

Power management circuit Technical field

The present application relates to the technical field of battery-powered equipment, and in particular, to a power management circuit.

Background technique

With the advancement of science and technology and the improvement of the quality of life, a variety of electronic equipment has emerged in various industries, and the demand for portable electronic equipment and mobile electronic equipment is increasing. For example, in the medical field, when the application range of medical equipment is extended from hospitals to emergency and home medical environments, its mobility and convenience will become particularly important and prominent; in addition, medical equipment in hospitals often also requires batteries Support, such as ultrasound equipment, blood analyzers, etc., to facilitate patient transfer in different wards. In this case, batteries are needed to power these electronic devices.

At present, for devices that require power supply, in order to support the switch management of the device, the device still needs a battery to power the switch management module (Microcontroller Unit (MCU) and its peripheral circuits) when the device is turned off. Now, although the switch management module has been designed with low power consumption, the switch management module will still be in the working state under the shutdown state, thereby continuously consuming the energy of the battery. In this way, when the device is stored for a long time, idle Or during transportation, the battery will always be discharged, which will cause the battery to over discharge or even damage the battery.

Summary of the Invention

The present application provides a power management circuit to realize the start-up and shutdown functions of a battery-powered device, and to reduce the power consumption of the battery when the battery-powered device is in a shutdown state.

According to a first aspect, an embodiment provides a power management circuit, including: a switch management module, a load switch, and a battery;

The battery includes a battery cell and a battery protection board, and the battery protection board is used to control the power output of the battery according to the input level signal;

The switch management module includes a power receiving end, a detection end, a first control end and a second control end;

The power receiving end is used to obtain the power input from the battery, and the detection end is used to detect the power-on or power-off signal;

The first control terminal is connected to the load switch, and the second control terminal is connected to the battery protection board;

When the switch management module detects a shutdown signal, the first control terminal outputs a first control signal to control the load switch to turn off and stop supplying power to the load; the second control terminal outputs a second control signal to control The battery protection board turns off the power output of the battery.

Further, when the switch-on management module detects a start-up signal, the first control terminal outputs a third control signal to control the load switch to close and provide power to the load; the second control terminal outputs a fourth control signal to The battery protection board is controlled to be turned on so that the battery maintains a state of outputting electric energy.

According to a second aspect, an embodiment provides a power management circuit, including: a switch management module, a load switch, a battery, and a switch circuit;

The switch circuit is connected between the battery and the switch management module, and the switch circuit is used to control the power output of the battery according to the input level signal;

The switch management module includes a power receiving end, a detection end, a first control end and a second control end;

The power receiving end is used to obtain the power input from the battery, and the detection end is used to detect the power-on or power-off signal;

The first control terminal is connected to the load switch, and the second control terminal is connected to the control terminal of the switch circuit;

When the switch management module detects a shutdown signal, the first control terminal outputs a first control signal to control the load switch to turn off and stop supplying power to the load; the second control terminal outputs a second control signal to control The switch circuit turns off the power output of the battery.

Further, when the switch-on management module detects a start-up signal, the first control terminal outputs a third control signal to control the load switch to close and provide power to the load; the second control terminal outputs a fourth control signal to The switch circuit is controlled to be turned on so that the battery maintains a state of outputting electric energy.

According to the power management circuit of the above embodiment, when the switch management module detects a shutdown signal, the load switch is controlled to turn off to stop supplying power to the load, and the battery protection board is controlled or connected between the battery and the switch management module. The switch circuit shuts off the power output of the battery; when the switch management module detects a shutdown signal, it controls the load switch to close to provide power to the load, and controls the battery protection board or the switch circuit connected between the battery and the switch management module. Power on to keep the battery outputting power. It realizes the start-up and shutdown management of battery-powered equipment. At the same time, the power-on / off management module no longer consumes battery power in the shutdown state, thereby reducing battery power consumption.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic structural diagram of a power management circuit according to an embodiment of the present invention;

2 is a schematic diagram of an internal structure of a battery according to an embodiment of the present invention;

3 is a schematic structural diagram of a specific power management circuit according to an embodiment of the present invention;

4 is a schematic structural diagram of another specific power management circuit according to an embodiment of the present invention;

5 is a schematic structural diagram of still another specific power management circuit according to an embodiment of the present invention;

6 is a flowchart of a startup process and a shutdown process according to an embodiment of the present invention;

FIG. 7a is a timing diagram of a boot process in an embodiment of the present invention; FIG.

7b is a timing diagram of a shutdown process in an embodiment of the present invention;

8 is a schematic structural diagram of a power management circuit according to another embodiment of the present invention;

9 is a schematic structural diagram of a specific power management circuit according to another embodiment of the present invention;

10 is a schematic structural diagram of another specific power management circuit according to another embodiment of the present invention;

11 is a schematic structural diagram of still another specific power management circuit according to another embodiment of the present invention;

FIG. 12 is a schematic structural diagram of still another specific power management circuit according to another embodiment of the present invention.

detailed description

The present application will be further described in detail below through specific embodiments in combination with the accompanying drawings. In the different embodiments, similar elements are labeled with associated similar elements. In the following embodiments, many details are described so that the present application can be better understood. However, those skilled in the art can effortlessly realize that some of these features can be omitted in different situations, or can be replaced by other elements, materials, and methods.

The serial numbers of components in this document, such as "first", "second", etc., are only used to distinguish the described objects and do not have any order or technical meaning. The terms “connection” and “connection” in this application include direct and indirect connections (connections) unless otherwise specified.

In the embodiment of the present application, when the power-on / off management module detects a shutdown signal, the first control terminal outputs a first control signal to control the load switch to turn off, stop supplying power to the load, and the second control terminal outputs a second control Signal to control the battery protection board to turn off the power output of the battery. Alternatively, a switch circuit is connected between the battery and the switch management module. When the switch management module detects a shutdown signal, the first control terminal outputs a first control signal to control the load switch to turn off and stop supplying power to the load. And the second control terminal outputs a second control signal to control the switching circuit to turn off the power output of the battery.

In one embodiment, a power management circuit is provided. For a schematic diagram of the power management circuit, refer to FIG. 1. The power management circuit includes a switch management module 1, a load switch 2, and a battery 3. The battery 3 includes a battery cell 31 and a battery protection board 32. The battery protection board 32 is used to control the power output of the battery 3 according to the input level signal. The switch management module 1 includes a power receiving terminal Vin, a detection terminal Key_N, a first A control terminal EN and a second control terminal Pwr_ON. The power receiving terminal Vin is connected to the output terminal Vout of the battery 3 to obtain the power of the battery 3. The detection terminal Key_N is used to detect the power-on or shutdown signal. The first control terminal EN The load switch 2 is connected, and the second control terminal Pwr_ON is connected to the battery protection board. When the switch management module 1 detects a shutdown signal, its first control terminal EN outputs a first control signal to control the load switch 2 to turn off and stop supplying power to the load. At the same time, its second control terminal Pwr_ON outputs a second control. The signal is used to control the battery protection board 32 to turn off the power output of the battery 3, so as to stop supplying power to the power-on / off management module 1. When the switch management module 1 detects the start-up signal, its first control terminal EN outputs a third control signal to control the load switch 2 to close, so that the battery 3 provides power to the load. At the same time, its second control terminal Pwr_ON outputs a fourth The control signal controls the battery protection board 32 to be turned on, so that the battery 3 maintains a state of outputting electric energy.

In the actual circuit design, a pull-up resistor R1 is also connected between the Key_N terminal and the power receiving terminal Vin, which is used to provide a pull-up voltage to the Key_N terminal to ensure that the Key_N terminal is high level in the shutdown state.

Specifically, the load switch 2 includes a power input terminal 21, a control terminal 22, and a power output terminal 23. The power input terminal 21 is connected to the output terminal Vout of the battery 3. The control terminal 22 is connected to the first control terminal EN of the switch management module 1. The power output terminal 23 is connected to the load. The load switch 2 is turned on when the control terminal 22 inputs a third control signal, so as to provide the power output from the battery 3 to the load.

Specifically, for the internal structure of the battery 3, refer to FIG. 2. As shown in FIG. 2, the battery 3 includes a battery cell 31 and a battery protection plate 32. The battery protection plate 32 is generally composed of a control chip B and a switch Q2. The switch Q2 is connected between the output terminal of the battery 31 and the output terminal Vout of the battery 3, and its control terminal d is connected to the control terminal e of the control chip B to be turned on or off under the control of the control terminal e; the control chip B is used to monitor the power of the battery 3, and by detecting the voltage, output current, and cell temperature of the battery 3, the switch Q2 is disconnected in the case of the battery 3 overvoltage, overcurrent, output short circuit, and overtemperature, so that It plays a role of protecting the battery 31. The control chip B may be, for example, a chip of type BQ20Z95DBT, and Q2 may be, for example, a MOS (Metal Oxide Semiconductor) field-effect transistor.

In this way, the enable terminal BAT_EN_N of the battery protection board can be led out, and the second control terminal Pwr_ON of the switch management module 1 controls the on or off of Q2 by controlling the enable terminal BAT_EN_N, so as to keep the battery 3 output The state of the power or the power output of the battery 3 is turned off. For example, when the control chip B of the battery protection board uses the chip BQ20Z95DBT, the in-position signal PRES of the chip can be used as the enable terminal BAT_EN_N. When the external circuit controls BAT_EN_N to be low level, the control chip B will control the switch Q2 to be turned on, so that the battery 3 will output power. When the external circuit controls BAT_EN_N to be in a high-impedance state, the control chip B controls the switch Q2 to be turned off. On, the battery 3 no longer outputs power, and at the same time, the battery protection board 32 enters a low power consumption mode.

In practical applications, the power management circuit further includes a power switch 4. For a schematic structural diagram of the power management circuit, see FIG. 3, where the power switch 4 includes a first terminal a1 and a second terminal a2, and the first terminal a1 is grounded. The second end a2 is connected to the battery protection board 32. The power switch 4 is used to connect the second end a2 to the ground when triggered, and disconnect the second end a2 from the ground after the trigger stops; the detection by the switch management module 1 The terminal Key_N is connected to the second terminal a2 of the power switch 4 and is used to detect a startup signal or a shutdown signal provided by the power switch. Specifically, the second terminal a2 of the power switch 4 is connected to the enable terminal BAT_EN_N of the battery protection board 32.

Based on the power management circuit shown in Figure 3, when the power switch 4 is triggered (that is, the power-on signal) when the power is turned on, the enable terminal BAT_EN_N of the battery protection board is instantly pulled down, that is, the enable terminal BAT_EN_N of the battery protection board is momentarily input Low level, at this time, the switching tube Q2 of the battery protection board 32 is turned on, and the battery 3 outputs power to apply a power supply voltage to the power supply terminal Vin of the switch management module 1. At this time, the switch management module 1 detects the start-up signal, and its second control terminal Pwr_ON outputs a fourth control signal to control the battery protection board 32 to keep on, so that the battery 3 is maintained in an output power state, so that the battery 3 continues. Provide power for the switch management module 1; at the same time, the first control terminal EN of the switch management module 1 outputs a third control signal to control the load switch 2 to close, so that the battery 3 provides power to the load, and the load equipment is turned on. When shutting down, the power switch 4 can be triggered for more than a predetermined time (that is, a shutdown signal). For example, the power switch 4 is triggered for more than 3 seconds. The shutdown signal can also be triggered by other methods, such as gesture triggering or voice triggering, which is not limited here. At this time, the switch management module 1 detects a shutdown signal in the power-on state, and its first control terminal EN outputs a first control signal to control the load switch 2 to turn off, the battery 3 stops supplying power to the load, and the load equipment is turned off; The second control terminal Pwr_ON outputs a second control signal to control the battery protection board 32 to turn off the power output of the battery 3, so that the battery 3 stops supplying power to the switch management module 1. At this time, the switch management module 1 no longer consumes batteries 3 power, battery 3 enters a low power state.

In practical applications, a conversion circuit can also be connected between the output terminal Vout of the battery 3 and the power receiving terminal Vin of the switch management module 1 to convert the voltage output by the battery 3 into the switch management suitable through the conversion circuit. Supply voltage of module 1.

The power management circuit provided in this embodiment controls the enable end of the battery protection board through the second control end of the power-on / off management module to enable the battery to output power to the outside or turn off the power output of the battery. When powering on, the power switch is triggered. The battery provides instantaneous power to the power management module. The power management module detects the power-on signal and controls the enable end of the battery protection board to maintain the power output state of the battery to make the battery power on and off. The management module continuously provides power, and at the same time controls the load switch to close to enable the battery to provide power to the load, thereby realizing the startup management of the load equipment. When shutting down, the power switch can be triggered for more than a predetermined time. At this time, the switch management module detects the shutdown signal, controls the load switch to turn off to stop the battery from supplying power to the load, and controls the enable end of the battery protection board to Turn off the battery to output power to the outside, so that the battery stops supplying power to the power management module, and the shutdown management of the load equipment is realized. By turning off the power output of the battery in the shutdown state, the battery no longer provides power to the power management module, so that the battery power consumption is minimized in the shutdown state, which maximizes the battery's power retention in the shutdown state Time is more conducive to long-term storage, transportation, and emergency use of battery-powered equipment.

In one embodiment, another specific power management circuit is provided. For a schematic structural diagram, refer to FIG. 4. Unlike FIG. 3, the power management circuit further includes a self-locking circuit 6. The self-locking circuit 6 is connected between the second control terminal Pwr_ON of the switch management module 1 and the enable terminal BAT_EN_N of the battery protection board 32, and is configured to respond to the fourth control signal output from the second control terminal Pwr_ON to the battery 3 The battery 3 is maintained in a state of outputting electric power, and the battery 3 is maintained in a state of turning off the power output in response to a second control signal output from the second control terminal Pwr_ON.

Specifically, in practical applications, the self-locking circuit 6 may be implemented by a first switching tube Q1, which is connected between the enable terminal BAT_EN_N of the battery protection board and the ground, and its control pole b and the switch management The second control terminal Pwr_ON of module 1 is connected, and Q1 can be turned on or off according to the control signal output from the second control terminal Pwr_ON to maintain the enable terminal BAT_EN_N of the battery protection board at a low level or a high impedance state, so that The battery 3 is maintained in a state of continuously outputting electric power or a state in which electric power output is turned off.

When the power-on / off management module detects the power-on signal, its second control terminal Pwr_ON outputs a fourth control signal to turn on Q1 to complete the power-on self-locking. At this time, Q1 remains on and enables the enable terminal of the battery protection board 32 BAT_EN_N is maintained in a low-level state, so that the battery 3 is maintained in a state of outputting electric energy, and the battery 3 continues to provide electric power to the power management module 1. When the switch management module detects the shutdown signal, its second control terminal Pwr_ON outputs a second control signal to release Q1 from the self-locking state. At this time, the enable terminal BAT_EN_N of the battery protection board 32 is in a high-impedance state, thereby protecting the battery. The board 32 turns off the power output of the battery 3, the battery 3 no longer provides power to the power-on / off management module 1, and the battery 3 enters a low power consumption state.

The battery management circuit provided in this embodiment controls the battery to output power or turns off the battery power output by controlling the enable signal of the battery protection board. When powering on, the self-locking circuit is powered on and self-locking, so that the enable end of the battery protection board is maintained at a low level, so that the battery continues to provide power to the power management module; when the power is off, the self-locking circuit releases self-locking. The enable end of the battery protection board becomes a high-impedance state, thereby turning off the power output of the battery, the battery no longer provides power for the power management module and enters a low power state, so that the battery power consumption is minimized in the off state .

In one embodiment, another specific power management circuit is provided. For a schematic structural diagram, refer to FIG. 5. Unlike the embodiment shown in FIG. 4, the power management circuit further includes a conversion circuit 5 and an isolation circuit 7. Among them, the enabling terminal BAT_EN_N of the battery protection board 32 is used as a control terminal for controlling the output power of the battery 3 and turning off the power output; the conversion circuit 5 is connected to the output terminal Vout of the battery protection board 32 and the power receiving terminal Vin of the switch management module 1 In between, the voltage output by the battery 3 can be converted into a power supply voltage adapted to the power-on / off management module 1. For example, the switch management module 1 is composed of an MCU (Microcontroller Unit), and its power supply voltage (that is, the operating voltage) is 3.3V. Then, the conversion circuit 5 converts the voltage output from the battery 3 into 3.3V and inputs it to The power receiving terminal Vin of the power-on / off management module 1 enables the power-on / off management module 1 to work normally. The self-locking circuit 6 includes a first switch Q1, which is connected between the enable terminal BAT_EN_N and the ground of the battery protection board 32, and a control electrode b thereof is connected to the second control terminal Pwr_ON of the switch management module 1 through a self-locking resistor R2. . The isolation circuit 7 includes a first diode D1 and a second diode D2. The anode of D1 is connected to the detection terminal Key_N of the switch management module 1, and the anode of D2 is connected to the enable terminals BAT_EN_N, D1 and D2 of the battery protection board 32. The cathode is connected to the second end a2 of the power switch 4, and the first end a1 of the power switch 4 is grounded. The isolation circuit 7 is used to isolate the signal at the detection terminal Key_N and the signal at the BAT_EN_N terminal to prevent mutual interference between the signal at the Key_N terminal and the signal at the BAT_EN_N terminal when the power switch 4 is released.

In the actual circuit design, a pull-up resistor R1 is also connected between the Key_N terminal and the power supply terminal Vin, which is used to provide a pull-up voltage to the Key_N terminal, and to ensure that the Key_N terminal is high when the power switch 4 is not triggered.

Based on the power management circuit shown in Figure 5, in practical applications, you can set the output terminal Vout to output power when the enable terminal BAT_EN_N is low, and set BAT_EN_N to high impedance to turn off Q2 to turn off the battery 3 Output and put the battery protection board 32 into a low power consumption state. FIG. 6 shows a flowchart of a startup process and a shutdown process, and FIG. 7a and FIG. 7b respectively show a sequence diagram of the startup process and a shutdown process. As shown in FIG. 6, the startup process includes processes ①, ②, and ③, and a shutdown process Including the processes ④ and ⑤, combined with FIG. 5 and FIG. 7a and FIG. 7b, the startup process is as follows:

① When powering on, press the power switch 4 (equivalent to a hard switch), D2 is turned on to ground BAT_EN_N. At this time, the BAT_EN_N terminal is low, and the output terminal Vout of the battery 3 outputs power. For the power supply voltage of the power management module 1, such as 3.3V, and input the power supply voltage to the power supply terminal Vin of the power management module 1, the power management module 1 sets the signal of the Pwr_ON terminal to high level as soon as the power is turned on. (Equivalent to soft switching), Q1 is turned on to complete power-on self-locking;

② At this time, Q1 will remain on, so that the output terminal Vout of the battery 3 maintains the state of outputting electric energy, and the battery 3 will continue to supply power to the switch management module 1;

③ The switch management module 1 controls the load switch 2 to be turned on through the EN terminal, that is, the main power switch in the device is turned on, thereby supplying power to the load and completing the turning on of the device.

The shutdown process is as follows:

④ When shutting down, long press the power switch 4, D1 is turned on and pull the Key_N terminal down. When the switch management module 1 detects that the Key_N terminal is pulled down for more than a predetermined time, for example, long press the power switch 4 for more than 3 seconds , The switch management module 1 detects that the Key_N terminal is pulled down for more than 3 seconds. At this time, the switch management module 1 will set the signal at the Pwr_ON terminal to low level, and at the same time control the load switch 2 to open through the EN terminal. Load provides power;

⑤ Q1 releases the self-locking state. When the power switch 4 is released, BA_EN_N is in a high-impedance state, Q2 is turned off, the output of battery 3 is turned off, and the battery protection board 32 enters a low power consumption state.

At this time, the external circuit of the battery 3 will no longer consume the power of the battery 3, that is, the current consumption of the external circuit is close to 0, so that the power consumption of the battery 3 is minimized in the off state, so that the power of the battery 3 can be maintained relatively The long time guarantees that the battery 3 can still be turned on normally after long-term storage.

The battery management circuit provided in this embodiment controls the battery to output power or turns off the battery power output by controlling the enable signal of the battery protection board. When starting up, through the combination of soft switches and hard switches, the enable end of the battery protection board is controlled to a low level to control the battery output power. When shutting down, through the combination of soft switches and hard switches, the enable end of the battery protection board is controlled to a high-impedance state to turn off the power output of the battery and put the battery protection board into a low power consumption state. On the one hand, the on / off management of the battery-powered equipment is realized; on the other hand, the power output of the battery is turned off in the off state, which minimizes the power consumption of the battery and maximizes the battery power retention time in the off state It is beneficial to long-term storage, transportation and emergency use of battery-powered equipment.

In practical applications, the power of the battery protection board inside the battery may not be turned off, but the switch circuit external to the battery may be used to turn on or off the battery and the external circuit. In one embodiment, FIG. 8 shows a schematic structural diagram of another power management circuit. The power management circuit includes a switch management module 1, a load switch 2, a battery 3, and a switch circuit 8. The switch circuit 8 is connected between the battery 3 and the switch management module 1 and is used to control the power output of the battery according to the input level signal. Specifically, the switch management module 1 includes a power receiving terminal Vin, a detection terminal Key_N, a first control terminal EN and a second control terminal Pwr_ON. The switch circuit 8 is connected to the output terminal Vout of the battery 3 and the power receiving of the switch management module 1 Between terminals Vin; the power receiving terminal Vin of the switch management module 1 is used to obtain the power input from the battery 3, the detection terminal Key_N is used to detect the power on or off signal, the first control terminal EN is connected to the load switch 2, and the second control terminal Pwr_ON It is connected to the control terminal c of the switching circuit 8. When the switch management module 1 detects a shutdown signal, its first control terminal EN outputs a first control signal to control the load switch 2 to turn off, so that the battery 3 stops supplying power to the load. At the same time, its second control terminal Pwr_ON outputs The second control signal is used to control the switch circuit 8 to turn off the power output of the battery 3, so as to stop the battery 3 from supplying power to the switch management module 1. When the switch management module 1 detects the start-up signal, its first control terminal EN outputs a third control signal to control the load switch 2 to close, so that the battery 3 provides power to the load. At the same time, its second control terminal Pwr_ON outputs a fourth The control signal is used to control the switch circuit 8 to be turned on, so that the battery 3 maintains the state of outputting electric power, and continuously supplies electric power to the switch management module 4.

In the actual circuit design, a pull-up resistor R1 is also connected between the Key_N terminal and the power receiving terminal Vin, which is used to provide a pull-up voltage to the Key_N terminal to ensure that the Key_N terminal is high level in the shutdown state.

Specifically, the load switch 2 includes an electric energy input terminal 21, a control terminal 22, and an electric energy output terminal 23. The electric energy input terminal 21 may be directly connected to the output terminal Vout of the battery 3 (as shown in FIG. 8), or may be connected through the switch circuit 8. It is connected to the output terminal Vout of the battery 3; its control terminal 22 is connected to the first control terminal EN of the switch management module 1, and the power output terminal 23 is connected to the load. When the load switch 2 inputs a third control signal to its control terminal 22 It is turned on to supply the electric power output from the battery 3 to the load.

In a practical application, the power management circuit further includes a power switch 4. For a schematic diagram of the structure, refer to FIG. 9, where the power switch 4 includes a first terminal a1 and a second terminal a2, a first terminal a1 of which is grounded and a second terminal a2. It is connected to the control terminal c of the switch circuit 8. The power switch 4 is used to connect the second terminal a2 to the ground when triggered, and to disconnect the second terminal a2 from the ground after the trigger is stopped. The detection terminal Key_N of the on / off management module 1 is connected to the second terminal a2 of the power switch 4 and is used to detect a start signal or a shutdown signal provided by the power switch 4.

Based on the power management circuit shown in FIG. 9, when the power switch 4 is triggered when the power is turned on, the control terminal c of the switch circuit 8 is pulled down momentarily, that is, the control terminal c is momentarily input to a low level. At this time, the switch circuit 8 is turned on, and the battery 3 and the switch management module 1 are connected. The battery 3 applies a power supply voltage to the power supply terminal Vin of the switch management module 1. At this time, the switch management module 1 detects the start-up signal, and its second control terminal Pwr_ON outputs a fourth control signal, and controls the switch circuit 8 to keep on, so that the battery 3 continues to provide power to the switch management module 1; at the same time, the switch The first control terminal EN of the machine management module 1 outputs a third control signal to control the load switch 2 to close, so that the battery 3 provides power to the load, and the load device is turned on. When shutting down, the power switch 4 can be triggered for more than a predetermined time. For example, the power switch 4 is triggered for more than 3 seconds. At this time, the switch management module 1 detects a shutdown signal when the power is on, and its first control terminal EN outputs The first control signal controls the load switch 2 to be turned off, the battery 3 stops supplying power to the load, and the load equipment is turned off; at the same time, the second control terminal Pwr_ON outputs a second control signal, and the control switch circuit 8 is turned off, so that the battery 3 stops as The on / off management module 1 provides power.

In practical applications, a conversion circuit can also be connected between the output terminal Vout of the battery 3 and the power receiving terminal Vin of the switch management module 1 to convert the voltage output by the battery 3 into the switch management suitable through the conversion circuit. Supply voltage of module 1.

In the power management circuit provided in this embodiment, a switch circuit is connected between the battery and the switch management module. The second control terminal of the switch management module controls the on / off of the switch circuit, so that the battery is the switch management module. Provides power or shuts down the power output of the battery. When powering on, the power switch is triggered. The battery provides instantaneous power to the power management module. The power management signal is detected by the power management module. The control circuit keeps the power on to enable the battery to continuously provide power to the power management module. The load provides power and realizes the startup management of the load equipment. When shutting down, the power switch can be triggered for more than a predetermined time. At this time, the switch management module detects a shutdown signal, controls the load switch to turn off to stop the battery from supplying power to the load, and controls the switch circuit to open to stop the battery. Provide power for the switch management module, and realize the shutdown management of the load equipment. By disconnecting the switch circuit in the off state, the battery no longer provides power to the power management module, so that the battery power consumption is minimized in the off state, which maximizes the battery's power retention time in the off state and more Conducive to long-term storage, transportation and use of battery-powered equipment in emergency situations.

In one embodiment, another specific power management circuit is provided. For a schematic structural diagram, refer to FIG. 10. Unlike FIG. 9, the power management circuit may further include a self-locking circuit 6. Among them, the self-locking circuit 6 is connected between the second control terminal Pwr_ON of the switch management module 1 and the control terminal c of the switch circuit 8, and is used to maintain the switch circuit 8 in response to a fourth control signal output from the second control terminal Pwr_ON. In the on state, the switch circuit 8 is maintained in the off state in response to a second control signal output from the second control terminal Pwr_ON. In practical applications, the switch circuit 8 may be set to be turned on when a low-level signal is input to the control terminal c thereof.

Specifically, the self-locking circuit 6 may be implemented by a first switching tube Q1, which is connected between the control terminal c of the switching circuit 8 and the ground, and the control electrode b of the first switching tube Q1 is connected to the second of the switch management module 1 The control terminal Pwr_ON is connected, and Q1 can be controlled to be turned on or off according to a control signal output from the second control terminal Pwr_ON to maintain the switch circuit 8 in an on state or an off state.

When the power-on / off management module 1 detects the power-on signal, its second control terminal Pwr_ON outputs a fourth control signal to turn on Q1 to complete the power-on self-lock. At this time, the switch circuit 8 remains on, and the battery 3 and the power The management module 1 is turned on, so that the battery 3 continues to provide power to the on / off management module 1. When the power-on / off management module 1 detects a shutdown signal, its second control terminal Pwr_ON outputs a second control signal to release Q1 from the self-locking state and maintain a high-impedance state, and the switch circuit 8 is turned off, thereby disconnecting the battery 3 and the power-on / off management module 1 When disconnected, the battery 3 no longer provides power to the power management module 1 and the battery 3 enters a low power consumption state.

The battery management circuit provided in this embodiment controls the on and off states of the switch circuit by controlling the self-locking circuit, thereby turning on or off the battery and the switch management module. When powering on, the self-locking circuit is powered on and self-locking to keep the switching circuit on, so that the battery continues to provide power to the switch management module. When the power is off, the self-locking circuit releases the self-locking and disconnects the switching circuit. No longer provides power for the switch management module and enters a low power consumption state, so that the power consumption of the battery can be minimized in the off state.

In one embodiment, another specific power management circuit is provided. For a schematic structural diagram, refer to FIG. 11. Unlike the embodiment shown in FIG. 10, the power management circuit further includes a conversion circuit 5 and an isolation circuit 7. The conversion circuit 5 is connected between the switch circuit 8 and the power receiving terminal Vin of the switch management module 1 for converting the voltage output by the battery 3 into a power supply voltage suitable for the switch management module 1. The self-locking circuit 6 includes a first A switch Q1 is connected between the control terminal c of the switch circuit 8 and the ground, and the control electrode b thereof is connected to the second control terminal Pwr_ON of the switch management module 1 through the self-locking resistor R2. The isolation circuit 7 includes a first diode D1 and a second diode D2, and the anode of D1 is connected to the detection terminal Key_N of the switch management module 1, the anode of D2 is connected to the control terminal c of the switch circuit 8, and the cathodes of D1 and D2 are connected At the second end a2 of the power switch 4, the first end a1 of the power switch 4 is grounded. The isolation circuit 7 is used to isolate the signal at the detection terminal Key_N and the signal at the BAT_EN_N terminal to prevent mutual interference between the signal at the Key_N terminal and the signal at the BAT_EN_N terminal when the power switch 4 is released.

In this embodiment, the power management circuit uses the second switching transistor Q3 as the switching circuit 8, and Q3 may be, for example, a MOS transistor. The power input terminal 21 of the load switch 2 is connected to the output terminal Vout of the battery through Q3, and the power input terminal 21 is connected to the input terminal of the conversion circuit 5. The first switch Q1 is connected to the control pole (that is, the control terminal c) of Q3 and the ground. Between them, the control of Q3 is connected to the anode of D2.

Based on the power management circuit shown in FIG. 11, when the power is turned on, the power switch 4 is pressed, and D2 is turned on to ground the control electrode c. At this time, the control electrode c is at a low level and Q3 is turned on so that the power output from the battery 3 can be provided to the conversion circuit 5. The conversion circuit 5 also converts the voltage of the power output from the battery 3 into the power supply voltage of the switch management module 1. For example 3.3V. Then, the power supply voltage is input to the power receiving terminal Vin of the switch management module 1. After the switch management module 1 is powered on, the signal at the Pwr_ON terminal is set to a high level, and Q1 is turned on to complete the power-on self-locking. At this time, Q1 remains in the on state, and the control electrode f is maintained at a low level, thereby maintaining the on state of Q3, so that the battery 3 can continue to supply power to the switch management module 1. After that, the switch management module 1 controls the load switch 2 to be turned on through the EN terminal, that is, the main power switch in the device is turned on, thereby turning on the device.

When shutting down, long press the power switch 1, D1 is turned on to pull the Key_N terminal low. When the switch management module 1 detects that the Key_N terminal has been pulled down for more than a predetermined time, that is, when a shutdown signal is detected, the Pwr_ON terminal is turned off. The signal is set to low level, and at the same time, the load switch 2 is controlled to be turned off through the EN terminal to stop supplying power to the load. At this time, Q1 is in a high-impedance state and self-locking is released. When the power switch 1 is released, Q3 is turned off, and the power transmission between the battery 3 and the external circuit is cut off. The current consumption of the external circuit is close to 0, and the battery enters a low power consumption state. Therefore, the power consumption of the battery 3 is minimized in the off state, and the power of the battery 3 can be maintained for a long time, thereby ensuring that the battery 3 can be normally turned on after long-term storage.

In the actual circuit design, Q3 can be connected to the battery 3 through the battery protection board 32. In this way, when the device is turned off, the power supply of the battery 3 to the internal battery protection board 32 may not be turned off, and the external power output of the battery 3 is cut off through Q3, so that the external power consumption of the battery 3 is minimized when the device is turned off.

The battery management circuit provided in this embodiment uses a second switching tube connected between the output end of the battery and the input end of the conversion circuit as the switching circuit, and the control electrode of the second switching tube is used as the control end of the switching circuit, and the power of the load switch is The input end is connected to the input end of the conversion circuit; when the power is turned on, the control of the second switch tube is controlled to a very low level through a combination of soft switches and hard switches, so that the second switch tube is turned on to provide power to the conversion circuit; When shutting down, the combination of soft and hard switches controls the control of the second switch tube to a very high-impedance state to disconnect the second switch tube, thereby cutting off the power transmission between the battery and the external circuit. On the one hand, the on-off management of battery-powered equipment is realized; on the other hand, the battery is put into a low-power state by shutting off the power transmission between the battery and external circuits in the off state, which prolongs the battery power in the off state Holding time is beneficial for long-term storage, transportation, and emergency use of battery-powered equipment.

In one embodiment, the power management circuit also uses the second switching transistor Q3 as the switching circuit 8, but is different from the embodiment shown in FIG. 11 in that the input terminal of the conversion circuit 5 is connected to the output terminal Vout of the battery 5 through Q3, and The power input terminal 21 of the load switch 2 is directly connected to the output terminal Vout of the battery 3, and its structure is shown in FIG. 12.

Based on the power management circuit shown in FIG. 12, the battery 3 can always provide power to the load switch 2. The signal at the EN terminal is used to control the load switch 2 to supply power to the load. The second switch Q3 only controls the output of the conversion circuit 5 and the battery 3. Connect or disconnect between terminals. Specifically, when Q3 is turned on, the Q3 is turned on so that the power output from the battery 3 can be provided to the conversion circuit 5, and when Q3 is turned off, the Q3 is turned off to cut off the power transmission between the battery 3 and the conversion circuit 5, so that the battery 3 enters Low power state.

The battery management circuit provided in this embodiment uses a second switching tube connected between the output end of the battery and the input end of the conversion circuit as the switching circuit, and the control electrode of the second switching tube is used as the control end of the switching circuit, and the power of the load switch is The input end is directly connected to the output end of the battery; when the power is turned on, the control of the second switch tube is controlled to a very low level through a combination of soft switches and hard switches, so that the second switch tube is turned on to provide power for the conversion circuit; When shutting down, through the combination of soft switches and hard switches, the control of controlling the second switch tube is extremely high-impedance state to disconnect the second switch tube, thereby cutting off the power transmission between the battery and the conversion circuit. On the one hand, the on / off management of the battery-powered equipment is realized; on the other hand, the battery enters a low power consumption state by cutting off the power transmission between the battery and the conversion circuit in the off state, which prolongs the battery power in the off state Holding time is beneficial for long-term storage, transportation, and emergency use of battery-powered equipment.

In the power management circuits of the above embodiments, a low-level signal is input to the enable end of the battery protection board or a low-level signal is input to the control end of the switch circuit. In the actual circuit design, the power management circuit also provides power. The battery protection board can be designed to enable the battery to output power when other signals are input, such as high-level signals; similarly, the switch circuit can also be turned on when other signals are input to its control terminal, such as when high-level signals are input. Turn on, not limited to low-level signals.

The above uses specific examples to explain this application, and is only used to help understand this application and is not intended to limit this application. For those skilled in the art to which this application belongs, according to the idea of this application, several simple deductions, deformations, or replacements can also be made.

Claims (17)

1. A power management circuit, comprising: a switch management module, a load switch, and a battery;

   The battery includes a battery cell and a battery protection board, and the battery protection board is used to control the power output of the battery according to an input level signal;

   The switch management module includes a power receiving end, a detection end, a first control end, and a second control end;

   The power receiving end is used to obtain the electric energy input by the battery, and the detection end is used to detect the power-on or power-off signal;

   The first control terminal is connected to the load switch, and the second control terminal is connected to the battery protection board;

   When the switch management module detects a shutdown signal, the first control terminal outputs a first control signal to control the load switch to turn off and stop supplying power to the load; the second control terminal outputs a second control A signal to control the battery protection board to turn off the power output of the battery.
2. The power management circuit according to claim 1, wherein when the power-on and power-off management module detects a power-on signal, the first control terminal outputs a third control signal to control the load switch to be closed, and is a load. Provide electric energy; the second control terminal outputs a fourth control signal to control the battery protection board to be turned on, so that the battery maintains a state of outputting electric energy.
3. The power management circuit according to claim 1, wherein the power management circuit further comprises a power switch, the power switch includes a first terminal and a second terminal, the first terminal is grounded, and the second terminal Connected to the battery protection board; the power switch is used to connect the second end to ground when triggered, and disconnect the second end from ground after the trigger stops;

   The detection terminal of the on / off management module is connected to the second terminal of the power switch, and is configured to detect a start-up or shutdown signal provided by the power switch.
4. The power management circuit according to claim 1, wherein the power management circuit further comprises a conversion circuit;

   The conversion circuit is connected between the output end of the battery and the power receiving end of the switch management module, and is used to convert the voltage output by the battery into a power supply voltage adapted to the switch management module.
5. The power management circuit according to any one of claims 1 to 4, wherein the power management circuit further comprises a self-locking circuit, the self-locking circuit is connected to the second control terminal of the power management module and the battery. Between the protection boards, the battery is maintained in a state of outputting electric energy in response to a fourth control signal output from the second control terminal, and the battery is maintained in a state of turning off the power output in response to a second control signal output from the second control terminal.
6. The power management circuit according to claim 5, wherein the self-locking circuit comprises a first switch tube connected between the battery protection board and the ground, a control pole of the first switch tube and a first switch management module. Two control terminals are connected.
7. The power management circuit according to any one of claims 1 to 4, wherein the load switch comprises an electric energy input terminal, a control terminal, and an electric energy output terminal, and the electric energy input terminal is connected to an output terminal of a battery, so that The control terminal is connected to the first control terminal of the switch management module, the power output terminal is connected to the load, and the load switch is turned on when the control terminal inputs a third control signal to provide the power output from the battery to the load. .
8. The power management circuit according to claim 3, wherein the power management circuit further comprises a first diode and a second diode, and an anode of the first diode is connected to a detection terminal of the power-on / off management module, The anode of the second diode is connected to the battery protection board, and the cathode of the first diode and the cathode of the second diode are connected to the second end of the power switch.
9. A power management circuit, comprising: a switch management module, a load switch, a battery, and a switch circuit;

   The switch circuit is connected between the battery and the switch management module, and the switch circuit is used to control the power output of the battery according to the input level signal;

   The switch management module includes a power receiving end, a detection end, a first control end, and a second control end;

   The power receiving end is used to obtain the electric energy input by the battery, and the detection end is used to detect the power-on or power-off signal;

   The first control terminal is connected to the load switch, and the second control terminal is connected to the control terminal of the switch circuit;

   When the switch management module detects a shutdown signal, the first control terminal outputs a first control signal to control the load switch to turn off and stop supplying power to the load; the second control terminal outputs a second control A signal to control the switching circuit to turn off the power output of the battery.
10. The power management circuit according to claim 9, wherein when the power-on and power-off management module detects a power-on signal, the first control terminal outputs a third control signal to control the load switch to be closed, and is a load. Provide electric energy; the second control terminal outputs a fourth control signal to control the switch circuit to be turned on, so that the battery maintains a state of outputting electric energy.
11. The power management circuit according to claim 9, wherein the power management circuit further comprises a power switch, the power switch includes a first terminal and a second terminal, the first terminal is grounded, and the second terminal Connected to the control end of the switching circuit; the power switch is used to connect the second end to ground when triggered, and disconnect the second end from ground after the trigger stops;

    The detection terminal of the on / off management module is connected to the second terminal of the power switch, and is configured to detect a start-up or shutdown signal provided by the power switch.
12. The power management circuit according to claim 9, wherein the power management circuit further comprises a conversion circuit, the conversion circuit is connected between the switch circuit and the power supply terminal of the switch management module, and is used for outputting the battery. The voltage is converted into a power supply voltage adapted to the power management module.
13. The power management circuit according to any one of claims 9 to 12, wherein the power management circuit further comprises a self-locking circuit, and the self-locking circuit is connected to the second control terminal and the switch of the power management module. Between the control terminals of the circuit, the switch circuit is maintained in an on state in response to a fourth control signal output from the second control terminal, and the switch circuit is maintained in an off state in response to a second control signal output from the second control terminal. .
14. The power management circuit according to claim 13, wherein the self-locking circuit comprises a first switch tube connected between a control terminal of the switch circuit and the ground, a control pole of the first switch tube and a switch management module. The second control terminal is connected.
15. The power management circuit according to any one of claims 9 to 12, wherein the switching circuit is a second switching tube.
16. The power management circuit according to claim 15, wherein the load switch comprises an electric energy input terminal, a control terminal, and an electric energy output terminal, and the electric energy input terminal is directly or through a second switch tube connected to the battery output terminal, The control terminal is connected to the first control terminal of the switch management module, the power output terminal is connected to the load, and the load switch is turned on when the control terminal inputs a third control signal to provide the power output from the battery to load.
17. The power management circuit according to claim 11, wherein the power management circuit further comprises a first diode and a second diode, and an anode of the first diode is connected to a detection terminal of the power management module, The anode of the second diode is connected to the control terminal of the switching circuit, and the cathode of the first diode and the cathode of the second diode are connected to the second terminal of the power switch.

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