A backup battery start and stop circuit

Abstract

The application discloses a kind of standby battery starting and shutdown circuit, including switch module, self-locking module, voltage reduction module, single-chip microcomputer, judging module, output module, the switch module with the self-locking module, the output module is connected respectively, the self-locking module with the voltage reduction module, the single-chip microcomputer, the judging module, the output module is connected, the voltage reduction module connects the single-chip microcomputer, the output module, the single-chip microcomputer connects the judging module, the output module, and the output terminal of the output module outputs output voltage.The standby battery starting and shutdown circuit of the application realizes zero leakage current in circuit after standby battery discharge termination, prevents damage caused by small current discharge after standby battery discharge termination.

Description

Technical Field

[0001] This invention relates to the field of power supply technology, and in particular to a backup battery start-up and shutdown circuit. Background Technology

[0002] In practical engineering applications, the time between product startup and final acceptance is often long. During this period, the product is usually unsupervised and prone to frequent power outages. After a power outage, the product's backup battery activates. Once the backup battery has finished discharging, the system disconnects it for protection. However, even after the backup battery is disconnected, leakage current remains in the circuit, causing a small current discharge to the backup battery. If the power outage is prolonged under these conditions, it can damage the backup battery. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides a backup battery start-up and shutdown circuit to prevent damage to the backup battery due to low-current discharge after the discharge process has ended.

[0004] To achieve the above objectives, the technical solution of the present invention is as follows:

[0005] A backup battery start-up and shutdown circuit includes a switch module, a self-locking module, a step-down module, a microcontroller, a judgment module, and an output module. The switch module is connected to the self-locking module and the output module respectively. The self-locking module is connected to the step-down module, the microcontroller, the judgment module, and the output module respectively. The step-down module is connected to the microcontroller and the output module. The microcontroller is connected to the judgment module and the output module. The output module outputs an output voltage.

[0006] The aforementioned self-locking module includes a first resistor, a second resistor, a first switch, and a second switch. The first terminal is connected to the source of the first switch, the drain of the first switch is connected to the first terminal of the first resistor, the second terminal of the first resistor is connected to the first terminal of the second resistor, the second terminal of the second resistor is connected to the gate of the second switch, the drain of the second switch is connected to the gate of the first switch, the source of the second switch is grounded, the second terminal of the second resistor is connected to the first terminal, the first terminal of the second resistor is connected to the second terminal, the gate of the second switch is connected to the first port of the microcontroller, and the drain of the first switch is connected to the third terminal.

[0007] The aforementioned backup battery start-up and shutdown circuit further includes a first power source, which is connected to the first terminal of the first resistor.

[0008] The aforementioned switch module includes a battery, a first fuse, and a first switch. The positive terminal of the battery is connected to the first end of the first fuse, the second end of the first fuse is connected to the first end of the first switch, the second end of the first switch is connected to the first terminal, and the negative terminal of the battery is grounded.

[0009] The aforementioned step-down module includes a first step-down chip, the second terminal is connected to the input terminal of the first step-down chip, the output terminal of the first step-down chip outputs a first voltage, and the ground terminal of the first step-down chip is grounded.

[0010] The aforementioned judgment module includes a third resistor and a fourth resistor. The third terminal is connected to the first terminal of the third resistor, the second terminal of the third resistor is connected to the first terminal of the fourth resistor, the second terminal of the fourth resistor is grounded, and the first terminal of the fourth resistor is connected to the second port of the microcontroller.

[0011] The above-mentioned output module includes a fifth resistor, a third switch, a fourth switch, and a first relay. The third terminal is connected to the first terminal of the fifth resistor, the second terminal of the fifth resistor is connected to the gate of the third switch, the third port of the microcontroller is connected to the gate of the third switch, the source of the third switch is grounded, the drain of the third switch is connected to the first terminal of the first relay coil, the second terminal of the first relay coil is connected to the second terminal, the first terminal of the first relay switch is connected to the first terminal, the second terminal of the relay switch is connected to the source of the fourth switch, and the drain of the fourth switch outputs the output voltage.

[0012] The first switching transistor is a P-type MOSFET, and the second switching transistor is an N-type MOSFET.

[0013] The third switch is an N-type MOSFET, and the fourth switch is a P-type MOSFET.

[0014] The aforementioned first voltage is connected to the microcontroller.

[0015] Beneficial effects: The backup battery start-up and shutdown circuit of the present invention achieves zero leakage current in the circuit after the backup battery discharges to completion, preventing damage to the backup battery due to small current discharge after the discharge ends.

[0016] To make the above-mentioned features and advantages of the invention more apparent and understandable, specific embodiments are described below, and detailed descriptions are provided in conjunction with the accompanying drawings. Attached Figure Description

[0017] Figure 1 This is a block diagram of a specific embodiment of a backup battery start-up and shutdown circuit according to the present invention.

[0018] Figure 2 for Figure 1 Circuit diagram of the switch module.

[0019] Figure 3 for Figure 1 Circuit diagram of the self-locking module.

[0020] Figure 4 for Figure 1 Circuit diagram of the step-down module.

[0021] Figure 5 for Figure 1 The circuit diagram of the judgment module.

[0022] Figure 6 for Figure 1 The circuit diagram of the output module.

[0023] In the accompanying drawings, similar reference numerals refer to the same elements. Detailed Implementation

[0024] To make the objectives and technical solutions of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0025] Figure 1 This is a block diagram of a specific embodiment of a backup battery start-up and shutdown circuit according to the present invention. Figure 1 As shown, a backup battery start-up and shutdown circuit includes a switch module 11, a self-locking module 12, a step-down module 13, a microcontroller 14, a judgment module 15, and an output module 16. The switch module 11 is connected to the self-locking module 12 and the output module 16 respectively. The self-locking module 12 is connected to the step-down module 13, the microcontroller 14, the judgment module 15, and the output module 16. The step-down module 13 is connected to the microcontroller 14 and the output module 16. The microcontroller 14 is connected to the judgment module 15 and the output module 16. The output terminal of the output module 16 outputs an output voltage V. O .

[0026] Figure 2 for Figure 1 The circuit diagram of the switch module 11 is shown below. Figure 2As shown, the switch module 11 includes a backup battery, a fuse F1, and a switch S1. The backup battery has a battery voltage of V1. The positive terminal of the battery voltage V1 is connected to the first terminal of the fuse F1, and the second terminal of the fuse F1 is connected to the first terminal of the switch S1. The second terminal of the switch S1 is terminal BAT. The negative terminal of the battery voltage V1 is grounded. The switch S1 is a backup power switch.

[0027] Figure 3 for Figure 1 The circuit diagram of the self-locking module 12 is shown below. Figure 3 As shown, the self-locking module 12 includes multiple resistors, multiple capacitors, multiple diodes, multiple switching transistors, and a Zener diode ZD1. Terminal BAT is connected to the source of switching transistor Q1. The drain of switching transistor Q1 is connected to the anode of diode D1. The cathode of diode D1 is connected to the first terminal of resistor R1. The second terminal of resistor R1 is connected to the first terminal of resistor R2. The second terminal of resistor R2 is connected to the gate of switching transistor Q2. The drain of switching transistor Q2 is connected to the first terminal of resistor R3. The second terminal of resistor R3 is connected to the gate of switching transistor Q1. The source of switching transistor Q2 is grounded. Resistor R4 is connected in parallel between the source and gate of switching transistor Q1. The anode of Zener diode ZD1 is connected to the gate of switching transistor Q1, and the cathode of Zener diode ZD1 is connected to the source of switching transistor Q1. Resistor R5 is connected in parallel between the gate and source of the switching transistor Q2. The second end of resistor R2 is connected to the first end of resistor R6. The second end of resistor R6 is connected to the negative terminal of capacitor C1. The positive terminal of capacitor C1 is connected to terminal BAT. Power supply V2 is connected to the anode of diode D2. The cathode of diode D2 is connected to the first end of resistor R1. The first end of resistor R2 is connected to the anode of diode D3. The cathode of diode D3 is terminal VCB. The positive terminal of capacitor C2 is connected to the cathode of diode D3. The negative terminal of capacitor C2 is grounded. The first end of resistor R6 is connected to the anode of diode D4. The cathode of diode D4 is connected to the anode of diode D5. The cathode of diode D5 is connected to voltage Vcc. The anode of diode D5 is connected to port GD2 of microcontroller 14. Switching transistor Q1 is a P-type MOSFET, switching transistor Q2 is an N-type MOSFET, capacitors C1 and C2 are electrolytic capacitors, and the drain of switching transistor Q1 is terminal BATA.

[0028] Figure 4 for Figure 1 A circuit diagram of the step-down module 13. (See diagram below.) Figure 4As shown, the step-down module 13 includes a step-down chip IC1 and multiple capacitors. The terminal VCB is connected to the input terminal IN of the step-down chip IC1. The output terminal OUT of the step-down chip IC1 outputs voltage Vcc to the self-locking module 12, the microcontroller 14, and the output module 16. The port COM of the step-down chip IC1 is grounded. Capacitor C3 is connected in parallel between the input terminal IN of the step-down chip IC1 and ground GND. Capacitor C4 is connected in parallel between the output terminal OUT of the step-down chip IC1 and ground GND. Capacitor C5 is connected in parallel across the two ends of capacitor C4. Capacitor C6 is connected in parallel across the two ends of capacitor C5.

[0029] Figure 5 for Figure 1 The circuit diagram of the judgment module 15 is shown below. Figure 5 As shown, the judgment module 15 includes resistor R7, resistor R8, and capacitor C7. The terminal BATA is connected to the first end of resistor R7, the second end of resistor R7 is connected to the first end of resistor R8, the second end of resistor R8 is grounded, capacitor C7 is connected in parallel across resistor R8, and the first end of resistor R8 is connected to port BS of the microcontroller 14.

[0030] Figure 6 for Figure 1 The circuit diagram of the output module 16 is shown below. Figure 6 As shown, the output module 16 includes a resistor R9, a capacitor C8, multiple diodes, multiple switching transistors, and a relay RL1. Terminal BATA is connected to the first end of the resistor R9, the second end of the resistor R9 is connected to the anode of diode D6, the cathode of diode D6 is connected to the anode of diode D7, the cathode of diode D7 is connected to the voltage Vcc, the cathode of diode D6 is connected to port GD1 of the microcontroller 14, the anode of diode D6 is connected to the gate of switching transistor Q3, the drain of switching transistor Q3 is terminal JIS, and the source of switching transistor Q3 is connected to the anode of diode D8. The cathode of transistor D8 is grounded. Capacitor C8 is connected in parallel between the gate and source of switching transistor Q3. The first terminal of the relay RL1 coil is connected to terminal VCB, and the second terminal of the relay RL1 coil is connected to terminal JIS. The anode of diode D9 is connected to the second terminal of the relay RL1 coil, and the cathode of diode D9 is connected to the first terminal of the relay RL1 coil. The first terminal of the relay RL1 switch is connected to terminal BAT, and the second terminal of the relay RL1 switch is terminal BK. Terminal BK is connected to the source of switching transistor Q4, and the drain of switching transistor Q4 outputs the output voltage V. O Among them, the switching transistor Q3 is an N-type MOSFET, and the switching transistor Q4 is an N-type MOSFET.

[0031] The following continues... Figures 1 to 6 The working principle of this invention is as follows: After the switch S1 is turned on, the battery voltage V1 is energized through the fuse F1, which powers the BAT network at the terminal. Once the BAT network is energized, there is voltage across the capacitor C1, creating a voltage difference between the gate and source of the switching transistor Q2. This causes the switching transistor Q2 to conduct, grounding the first terminal of the resistor R3 and turning on the switching transistor Q1. Consequently, a voltage is generated at the terminal VCB at the terminal BAT through the switching transistor Q1, the diode D1, the resistor R1, and the diode D3. Furthermore, because there is voltage at the connection point between the resistor R1 and the anode of the diode D3, the switching transistor Q2 remains on, thus self-locking the self-locking module 12 and maintaining a constant voltage at the terminal VCB. The potential of the terminal BAT is approximately equal to the potential of the terminal BAT, and the potential of the terminal VCB is approximately equal to the potential of the terminal BAT. The power supply V2 is a DC voltage output from rectified AC mains power, allowing the backup battery start-up and shutdown circuits to be started via AC mains power. After the terminal VCB is energized, the voltage Vcc is obtained through the step-down chip IC1, providing power to the microcontroller 14 and enabling it to operate. The voltage at the terminal BATA is divided by resistors R7 and R8, resulting in a voltage V at the port BS of the microcontroller 14. BS The microcontroller 14, based on the sampled voltage V BS Determine whether the voltage of the terminal BAT is within the voltage range set by the software program of the microcontroller 14, that is, whether the battery voltage V1 is within the set voltage range.

[0032] When the battery voltage V1 is within the set voltage range, the microcontroller 14 outputs a high level to the output module 16 via port GD1, the switching transistor Q3 is turned on, and the terminal JIS is connected to ground GND through the switching transistor Q3 and the diode D8. At this time, a voltage approximately equal to the battery voltage V1 is formed across the coil of the relay RL1, and the relay RL1 is activated, causing the terminal BAT to connect to the terminal BK. The terminal BK outputs the output voltage V through the switching transistor Q4. O .

[0033] When the battery voltage V1 is not within the set voltage range, the microcontroller 14 outputs a low level at port GD1, causing the switching transistor Q3 to turn off, thereby disconnecting the relay RL1 and ceasing to output the output voltage V. OThe backup battery stops supplying power to the load. However, at this time, the switch S1 is not yet turned off, and the self-locking module 12 is still in a self-locking state, still discharging the battery. Therefore, the present invention sets a timing period T1 through the microcontroller 14, and starts timing when the battery voltage V1 is not in the set voltage range. When the timing period T1 is completed, the port GD2 of the microcontroller 14 is made low, thereby turning off the switch Q2 of the self-locking module 12, and the self-locking module 12 is released from self-locking, realizing zero leakage current in the circuit.

[0034] In summary, the backup battery start-up and shutdown circuit of the present invention relies on the microcontroller 14 to realize the software start-up and software shutdown of the backup battery, achieving zero leakage current in the circuit after the backup battery stops supplying power to the load, and preventing damage to the backup battery due to small current discharge after the discharge ends.

[0035] Although the present invention has been disclosed above by way of embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make some modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A backup battery start-up and shutdown circuit, characterized in that, The system includes a switch module, a self-locking module, a step-down module, a microcontroller, a judgment module, and an output module. The switch module is connected to the self-locking module and the output module respectively. The self-locking module is connected to the step-down module, the microcontroller, the judgment module, and the output module respectively. The step-down module is connected to the microcontroller and the output module. The microcontroller is connected to the judgment module and the output module. The output module outputs an output voltage at its output terminal. The self-locking module includes a first resistor, a second resistor, a first switch, and a second switch. The first terminal is connected to the source of the first switch, the drain of the first switch is connected to the first terminal of the first resistor, the second terminal of the first resistor is connected to the first terminal of the second resistor, the second terminal of the second resistor is connected to the gate of the second switch, the drain of the second switch is connected to the gate of the first switch, the source of the second switch is grounded, the second terminal of the second resistor is connected to the first terminal, the first terminal of the second resistor is connected to the second terminal, the gate of the second switch is connected to the first port of the microcontroller, and the drain of the first switch is connected to the third terminal. The output module includes a fifth resistor, a third switch, a fourth switch, and a first relay. The third terminal is connected to the first terminal of the fifth resistor, the second terminal of the fifth resistor is connected to the gate of the third switch, the third port of the microcontroller is connected to the gate of the third switch, the source of the third switch is grounded, the drain of the third switch is connected to the first terminal of the first relay coil, the second terminal of the first relay coil is connected to the second terminal, the first terminal of the first relay switch is connected to the first terminal, the second terminal of the first relay switch is connected to the source of the fourth switch, and the drain of the fourth switch outputs the output voltage. The microcontroller is configured such that when the battery voltage is within a set voltage range, the third port of the microcontroller outputs a high level to turn on the third switch, activates the first relay, and the output module outputs voltage; a timer is set, and when the battery voltage is outside the set voltage range, the third port of the microcontroller outputs a low level to turn off the third switch, disconnects the first relay, stops outputting voltage, and the microcontroller starts timing; when the timing is complete, the first port of the microcontroller outputs a low level to turn off the second switch, and the self-locking module releases its self-lock.

2. The backup battery start-up and shutdown circuit as described in claim 1, characterized in that, It also includes a first power source, which is connected to the first terminal of the first resistor.

3. The backup battery start-up and shutdown circuit as described in claim 1, characterized in that, The switch module includes a battery, a first fuse, and a first switch. The positive terminal of the battery is connected to the first end of the first fuse, the second end of the first fuse is connected to the first end of the first switch, the second end of the first switch is connected to the first terminal, and the negative terminal of the battery is grounded.

4. The backup battery start-up and shutdown circuit as described in claim 1, characterized in that, The step-down module includes a first step-down chip, the second terminal is connected to the input terminal of the first step-down chip, the output terminal of the first step-down chip outputs a first voltage, and the ground terminal of the first step-down chip is grounded.

5. The backup battery start-up and shutdown circuit as described in claim 1, characterized in that, The judgment module includes a third resistor and a fourth resistor. The third terminal is connected to the first terminal of the third resistor, the second terminal of the third resistor is connected to the first terminal of the fourth resistor, the second terminal of the fourth resistor is grounded, and the first terminal of the fourth resistor is connected to the second port of the microcontroller.

6. The backup battery start-up and shutdown circuit as described in claim 1, characterized in that, The first switching transistor is a P-type MOSFET, and the second switching transistor is an N-type MOSFET.

7. The backup battery start-up and shutdown circuit as described in claim 1, characterized in that, The third switch is an N-type MOSFET, and the fourth switch is a P-type MOSFET.

8. The backup battery start-up and shutdown circuit as described in claim 4, characterized in that, The first voltage is connected to the microcontroller.

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