Energy storage circuit with isolation function

Abstract

The application provides an energy storage circuit with an isolation function, which comprises a power supply, a first signal generation module, a chip and an energy storage module. The power supply outputs a first voltage, and the first signal generation module generates a first signal. Based on the first signal, the chip outputs a first driving signal. Based on a driving voltage output by the energy storage module, the chip outputs a second driving signal. The energy storage module receives the first driving signal, and based on the first driving signal, the energy storage module receives and stores the first voltage. Based on the first driving signal and the second driving signal, the energy storage module converts the first voltage into a second voltage, and the energy storage module stores the second voltage.

Description

[0001] This application is a divisional application of the invention patent with application number "202111328659.6", application date "2021.11.10", and title "MOS transistor driving circuit". Technical Field

[0002] This invention relates to the field of circuits, and in particular to a driving circuit. Background Technology

[0003] In modern society, electronic devices require switching control of the power supply. Existing driver circuits often use dedicated chips to control the high-side MOSFETs. However, because dedicated chips are expensive and have a narrow range of applications, existing driver circuits suffer from high costs.

[0004] Therefore, it is necessary to provide a MOS transistor driving circuit to solve the above-mentioned technical problems. Summary of the Invention

[0005] This invention provides a MOSFET driving circuit that effectively solves the technical problem of high cost of existing driving circuits.

[0006] This invention provides a MOS transistor driving circuit, comprising:

[0007] The power supply is used to output the first voltage;

[0008] A first signal generation module is used to generate a first signal;

[0009] A chip that receives the first signal, outputs the first driving signal based on the first signal, and outputs the second driving signal based on the driving voltage output by the energy storage module;

[0010] The energy storage module receives the first drive signal, receives and stores the first voltage based on the first drive signal, converts the first voltage into a second voltage based on the first drive signal and the second drive signal, and stores the second voltage.

[0011] The control module is used to output control signals; and,

[0012] The driving module, based on the control signal and the second voltage released by the energy storage module, outputs a third driving signal to the gate of the MOS transistor group. The third driving signal is used to control the MOS transistor group to turn on and off, thereby the MOS transistor group controls the battery pack to output voltage to the load.

[0013] The chip includes an input pin and a low-side output pin. The energy storage module includes a first MOSFET and a first capacitor. The input pin is connected to the first signal generation module and is used to receive the first signal. The low-side output pin is connected to the gate of the first MOSFET and is used to output the first drive signal. The source of the first MOSFET is grounded, and the drain of the first MOSFET is connected to the first capacitor. The first capacitor is connected to the power supply.

[0014] When the low-side output pin outputs a high-level first drive signal, the gate of the first MOS transistor receives the high-level first drive signal, the first MOS transistor is turned on, and the first capacitor receives and stores the first voltage.

[0015] The chip includes a high-side output pin, a high-side floating absolute voltage pin, and a high-side floating offset voltage pin. The energy storage module also includes a second MOSFET and a second capacitor. The source of the second MOSFET is connected to the first capacitor, the drain of the second MOSFET is connected to one end of the second capacitor, the other end of the second capacitor is connected to the first capacitor, and the gate of the second MOSFET is connected to the high-side output pin, which is used to output the second drive signal. The high-side floating absolute voltage pin is connected to one end of the first capacitor and is used to receive the drive voltage. The high-side floating offset voltage pin is connected to the other end of the first capacitor and is used to isolate the first capacitor from the gate of the second MOSFET.

[0016] When the low-side output pin outputs a low-level first drive signal, the gate of the first MOS transistor receives the low-level first drive signal, and the first MOS transistor is turned off.

[0017] When the first capacitor outputs the driving voltage, the high-side floating absolute voltage pin receives the driving voltage, and the high-side output pin outputs the second driving signal. Based on the second driving signal, the second MOS transistor is turned on, so that the first capacitor outputs the first voltage. The energy storage module converts the first voltage into a second voltage, so that the second capacitor receives and stores the second voltage.

[0018] The energy storage module further includes a first diode and a second diode. The positive terminal of the first diode is connected to a power source, and the negative terminal of the first diode is connected to the first capacitor. The positive terminal of the second diode is connected to the first capacitor, and the negative terminal of the second diode is connected to the second capacitor.

[0019] The driving module includes a first driving unit and a second driving unit. The second driving unit includes an input terminal, an output terminal, and a control terminal. One end of the first driving unit is connected to the control module, and the other end of the first driving unit is connected to the control terminal. The input terminal is connected to the second capacitor, and the output terminal is connected to the gate of the MOS transistor group. The second driving unit outputs the third driving signal to the gate of the MOS transistor group and performs voltage following on the third driving signal.

[0020] The first driving unit includes a first optocoupler and a second optocoupler, the second driving unit includes a first transistor, a second transistor, a third transistor, and a fourth transistor, the MOS transistor group includes a third MOS transistor and a fourth MOS transistor, the positive terminal of the first optocoupler input terminal is connected to the control module, the negative terminal of the first optocoupler input terminal is grounded, the collector of the first optocoupler output terminal is connected to the second capacitor, and the emitter of the first optocoupler output terminal is connected to the base of the first transistor and the second transistor respectively;

[0021] The positive terminal of the second optocoupler input is connected to the control module, the negative terminal of the second optocoupler input is grounded, the collector of the second optocoupler output is connected to the second capacitor, and the emitter of the second optocoupler output is connected to the base of the third transistor and the fourth transistor, respectively.

[0022] The collector of the first transistor is connected to the second capacitor, the emitter of the first transistor is connected to the gate of the third MOS transistor and the emitter of the second transistor, the collector of the second transistor is grounded, the collector of the fourth transistor is connected to the second capacitor, the emitter of the fourth transistor is connected to the gate of the fourth MOS transistor and the emitter of the third transistor, and the collector of the third transistor is grounded.

[0023] The energy storage module includes a filtering unit for filtering the first voltage. The filtering unit includes a filtering capacitor, one end of which is connected between the power supply and the positive terminal of the first diode, and the other end of which is grounded.

[0024] In the MOS transistor driving circuit of the present invention, the MOS transistor driving circuit includes:

[0025] The power supply is used to output the first voltage;

[0026] A first signal generation module is used to generate a first signal;

[0027] A chip that receives the first signal, outputs the first driving signal based on the first signal, and outputs the second driving signal based on the driving voltage output by the energy storage module;

[0028] The energy storage module receives the first drive signal, receives and stores the first voltage based on the first drive signal, converts the first voltage into a second voltage based on the first drive signal and the second drive signal, and stores the second voltage.

[0029] The control module is used to output control signals; and,

[0030] The driving module, based on the control signal and the second voltage released by the energy storage module, outputs a third driving signal to the gate of the MOS transistor group. The third driving signal is used to control the MOS transistor group to turn on and off, thereby the MOS transistor group controls the battery pack output voltage to the load.

[0031] In the MOS transistor driving circuit of the present invention, the chip includes an input pin and a low-side output pin. The energy storage module includes a first MOS transistor and a first capacitor. The input pin is connected to the first signal generation module and is used to receive the first signal. The low-side output pin is connected to the gate of the first MOS transistor and is used to output the first driving signal. The source of the first MOS transistor is grounded, and the drain of the first MOS transistor is connected to the first capacitor. The first capacitor is connected to the power supply.

[0032] In the MOS transistor driving circuit of the present invention, when the low-side output pin outputs a high-level first driving signal, the gate of the first MOS transistor receives the high-level first driving signal, the first MOS transistor is turned on, and the first capacitor receives and stores the first voltage.

[0033] In the MOS transistor driving circuit of the present invention, the chip includes a high-side output pin, a high-side floating absolute voltage pin, and a high-side floating offset voltage pin. The energy storage module further includes a second MOS transistor and a second capacitor. The source of the second MOS transistor is connected to the first capacitor, the drain of the second MOS transistor is connected to one end of the second capacitor, the other end of the second capacitor is connected to the first capacitor, and the gate of the second MOS transistor is connected to the high-side output pin. The high-side output pin is used to output the second driving signal. The high-side floating absolute voltage pin is connected to one end of the first capacitor and is used to receive the driving voltage. The high-side floating offset voltage pin is connected to the other end of the first capacitor and is used to isolate the first capacitor from the gate of the second MOS transistor.

[0034] In the MOS transistor driving circuit of the present invention, when the low-side output pin outputs a low-level first driving signal, the gate of the first MOS transistor receives the low-level first driving signal, and the first MOS transistor is turned off.

[0035] When the first capacitor outputs the driving voltage, the high-side floating absolute voltage pin receives the driving voltage, and the high-side output pin outputs the second driving signal. Based on the second driving signal, the second MOS transistor is turned on, so that the first capacitor outputs the first voltage. The energy storage module converts the first voltage into a second voltage, so that the second capacitor receives and stores the second voltage.

[0036] In the MOS transistor driving circuit of the present invention, the energy storage module further includes a first diode and a second diode. The anode of the first diode is connected to the power supply, and the cathode of the first diode is connected to the first capacitor. The anode of the second diode is connected to the first capacitor, and the cathode of the second diode is connected to the second capacitor. The first diode is used to prevent the first capacitor from reverse charging the power supply, and the second diode is used to prevent the second capacitor from reverse charging the first capacitor.

[0037] In the MOS transistor driving circuit of the present invention, the driving module includes a first driving unit and a second driving unit. The second driving unit includes an input terminal, an output terminal, and a control terminal. One end of the first driving unit is connected to the control module, and the other end of the first driving unit is connected to the control terminal. The input terminal is connected to the second capacitor, and the output terminal is connected to the gate of the MOS transistor group. Based on the control signal and the second voltage released by the second capacitor, the second driving unit outputs the third driving signal to the gate of the MOS transistor group and performs voltage following on the third driving signal.

[0038] In the MOS transistor driving circuit of the present invention, the first driving unit includes a first optocoupler and a second optocoupler, the second driving unit includes a first transistor, a second transistor, a third transistor, and a fourth transistor, the MOS transistor group includes a third MOS transistor and a fourth MOS transistor, the positive terminal of the first optocoupler input terminal is connected to the control module, the negative terminal of the first optocoupler input terminal is grounded, the collector of the first optocoupler output terminal is connected to the second capacitor, and the emitter of the first optocoupler output terminal is connected to the base of the first transistor and the second transistor respectively;

[0039] The positive terminal of the second optocoupler input is connected to the control module, the negative terminal of the second optocoupler input is grounded, the collector of the second optocoupler output is connected to the second capacitor, and the emitter of the second optocoupler output is connected to the base of the third transistor and the fourth transistor, respectively.

[0040] The collector of the first transistor is connected to the second capacitor, the emitter of the first transistor is connected to the gate of the third MOS transistor and the emitter of the second transistor, the collector of the second transistor is grounded, the collector of the fourth transistor is connected to the second capacitor, the emitter of the fourth transistor is connected to the gate of the fourth MOS transistor and the emitter of the third transistor, and the collector of the third transistor is grounded.

[0041] In the MOS transistor driving circuit of the present invention, the energy storage module includes a filtering unit, which is used to filter the first voltage. The filtering unit includes a filtering capacitor, one end of which is connected between the power supply and the positive terminal of the first diode, and the other end of which is grounded.

[0042] Compared to existing technologies, the advantages of this invention are as follows: This invention provides a MOSFET driving circuit, which includes an energy storage module. Based on a first driving signal output by a chip, the energy storage module receives and stores a first voltage output by a power source. Based on the first and second driving signals output by the chip, the energy storage module converts the first voltage into a second voltage and stores the second voltage. Based on a control signal output by a control module and the second voltage released by the energy storage module, the driving module outputs a third driving signal to the gate of the MOSFET group. The third driving signal can control the MOSFET group to turn on and off, thereby controlling the battery pack output voltage to the load. Because the driving module can output the third driving signal based on the control signal and the second voltage, and the third driving signal can control the MOSFET group to turn on and off, this MOSFET driving circuit does not require a dedicated chip to control the high-side MOSFETs, thus reducing the cost of the MOSFET driving circuit. This effectively solves the technical problem of high cost in existing driving circuits, and the MOSFET driving circuit controls the battery pack output voltage through the MOSFET group, making the use of the battery pack safer.

[0043] This MOSFET driver circuit uses fewer components and has a simpler control scheme, thus offering advantages such as low cost and ease of implementation. Furthermore, completely disconnecting the positive terminal of the battery pack is safer than previous methods that controlled the negative terminal. The use of discrete components allows for greater flexibility in component selection and simplifies implementation. Attached Figure Description

[0044] Figure 1 This is a block diagram of an embodiment of the MOS transistor driving circuit of the present invention.

[0045] Figure 2 This is a circuit diagram of an embodiment of the MOS transistor driving circuit of the present invention.

[0046] In the figure, 10 is the MOSFET driving circuit; 11 is the power supply; 12 is the first signal generation module; 13 is the energy storage module; 131 is the filtering unit; 14 is the control module; 15 is the driving module; 151 is the first driving unit; 152 is the second driving unit; and 16 is the MOSFET group. Detailed Implementation

[0047] 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 embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0048] The directional terms mentioned in this invention, such as "up", "down", "front", "back", "left", "right", "inner", "outer", "side", "top" and "bottom", are only for reference to the orientation of the accompanying drawings. The directional terms used are for the purpose of explaining and understanding this invention, and are not intended to limit this invention.

[0049] The terms "first" and "second" used in the terminology of this invention are for descriptive purposes only and should not be construed as indicating or implying relative importance, nor as limiting the order of events.

[0050] Please refer to Figures 1 to 2 , Figure 1 This is a block diagram of an embodiment of the MOS transistor driving circuit of the present invention; Figure 2 This is a circuit diagram of an embodiment of the MOS transistor driving circuit of the present invention.

[0051] In the diagram, units with similar structures are represented by the same labels.

[0052] Please refer to Figure 1 and Figure 2 This invention provides a MOSFET driving circuit 10, which is applied in a battery pack. The MOSFET driving circuit includes a power supply 11, a first signal generation module 12, a chip U1, an energy storage module 13, a control module 14, and a driving module 15. The power supply 11 is a 12V power supply and can be used to output a first voltage.

[0053] Please refer to Figure 1 and Figure 2 The first signal generation module 12 is used to generate a first signal. This first signal generation module 12 includes a signal generator U2, a first resistor R3, a second resistor R4, a third resistor R5, a fourth resistor R8, a third capacitor C5, and a fourth capacitor C4. The signal generator U2, the first resistor R3, the second resistor R4, the third resistor R5, the fourth resistor R8, and the third capacitor C5 form a square wave generator; therefore, the duty cycle of the output signal of the first signal generation module 12 is 50%. Specifically, the positive input terminal of the signal generator U2 is connected to one end of the first resistor R3, and the other end of the first resistor R3 is grounded. The negative input terminal of the signal generator U2 is connected to one end of the third capacitor C5, and the other end of the third capacitor C5 is grounded. The V+ terminal of the signal generator U2 is connected to a power supply, and the V- terminal of the signal generator U2 is grounded. One end of the third resistor R5 is connected to a power supply, and the other end of the third resistor R5 is connected to the first resistor R3. One end of the second resistor R4 is connected to the third resistor R5, and the other end of the second resistor R4 is connected to the output terminal of the signal generator U2. One end of the fourth capacitor C4 is connected to the power supply, and the other end of the fourth capacitor C4 is grounded.

[0054] Please refer to Figure 1 and Figure 2 Chip U1 receives a first signal. Based on the first signal, chip U1 outputs a first drive signal. Chip U1 is a half-bridge driver chip. Energy storage module 13 receives the first drive signal and, based on the first drive signal, receives and stores a first voltage. Based on the first drive signal and a second drive signal, energy storage module 13 converts the first voltage into a second voltage and stores the second voltage.

[0055] Please refer to Figure 1 and Figure 2 The chip U1 includes an input pin IN and a low-side output pin LO. The energy storage module 13 includes a first MOSFET Q1 and a first capacitor C1. The input pin IN is connected to the first signal generation module 12 and is also connected to the output of the signal generator U2. The input pin IN can be used to receive a first signal. The low-side output pin LO is connected to the gate of the first MOSFET Q1 and can be used to output a first drive signal. The source of the first MOSFET Q1 is grounded, and the drain of the first MOSFET Q1 is connected to the first capacitor C1. The first capacitor C1 is connected to the power supply 11. The chip U1 also includes a VCC pin, an SD pin, and a GND pin. The VCC pin is connected to the power supply 11, the SD pin is floating, and the GND pin is grounded.

[0056] Please refer to Figure 1 and Figure 2 When the low-side output pin LO outputs a high-level first drive signal, the gate of the first MOSFET Q1 receives the high-level first drive signal. The first MOSFET Q1 is turned on, so the first capacitor C1 receives and stores the first voltage output by the power supply 11.

[0057] Please refer to Figure 1 and Figure 2 Based on the driving voltage output by the energy storage module 13, chip U1 outputs a second driving signal. Chip U1 also includes a high-side output pin H0, a high-side floating absolute voltage pin VB, and a high-side floating offset voltage pin VS. The energy storage module 13 also includes a second MOSFET Q2 and a second capacitor C2. The source of the second MOSFET Q2 is connected to the first capacitor C1, the drain of the second MOSFET Q2 is connected to one end of the second capacitor C2, and the other end of the second capacitor C2 is connected to the first capacitor C1. The gate of the second MOSFET Q2 is connected to the high-side output pin HO, which is used to output the second driving signal. The high-side floating absolute voltage pin VB is connected to one end of the first capacitor C1 and is used to receive the driving voltage. The high-side floating offset voltage pin VS is connected to the other end of the first capacitor C1 and can be used to isolate the first capacitor C1 from the gate of the second MOSFET Q2.

[0058] Please refer to Figure 1 and Figure 2 When the low-side output pin LO outputs a low-level first drive signal, the gate of the first MOSFET Q1 receives the low-level first drive signal, and the first MOSFET Q1 is turned off. When the first capacitor C1 outputs a drive voltage, the high-side floating absolute voltage pin VB receives the drive voltage, and the high-side output pin HO outputs a second drive signal. Based on the second drive signal, the second MOSFET Q2 is turned on, thereby the first capacitor C1 outputs a first voltage. The energy storage module 13 converts the first voltage into a second voltage, thereby the second capacitor C2 receives and stores the second voltage.

[0059] Please refer to Figure 1 and Figure 2 The energy storage module 13 also includes a first diode D1 and a second diode D2. The anode of the first diode D1 is connected to the power supply 11, and the cathode of the first diode D1 is connected to the first capacitor C1. The first diode D1 can be used to prevent the first capacitor C1 from reverse charging the power supply, and the setting of the first diode D1 can protect the power supply 11. The anode of the second diode D2 is connected to the first capacitor C1, and the cathode of the second diode D2 is connected to the second capacitor C2. The second diode D2 can be used to prevent the second capacitor C2 from reverse charging the first capacitor C1, and the setting of the second diode D2 can protect the first capacitor C1. A floating charge pump composed of the first MOSFET Q1, the second MOSFET Q2, the first diode D1, the second diode D2, the first capacitor C1, and the second capacitor C2 can be used to provide a second voltage to the drive module 15. The drive module 15 outputs a third drive signal based on the second voltage and the control signal output by the control module 14. The third drive signal can be used to control the conduction and cutoff of the MOSFET group 16, which is the high-side switch of the battery pack.

[0060] Please refer to Figure 1 and Figure 2 The energy storage module 13 includes a filter unit 131. The filter unit 131 filters the first voltage output by the power supply, and the filter capacitor C3 makes the first voltage less susceptible to noise interference. The filter unit includes a filter capacitor C3, one end of which is connected between the power supply 11 and the positive terminal of the first diode D1, and the other end of which is grounded. The energy storage module 13 also includes a fifth resistor R1 and a sixth resistor R2. The fifth resistor R1 is connected between the gate and source of the first MOSFET Q1. One end of the sixth resistor R2 is connected to the high-side floating offset voltage pin VS, and the other end of the sixth resistor R2 is connected to the source of the second MOSFET Q2.

[0061] Please refer to Figure 1 and Figure 2The control module 14 is used to output control signals. The control module 14 includes a first control terminal DSG and a second control terminal CHG, both of which can output control signals. Based on the control signals and the second voltage released by the energy storage module 13, the drive module 15 outputs a third drive signal to the gate of the MOSFET group 16. The third drive signal can be used to control the MOSFET group 16 to turn on and off, thereby the MOSFET group 16 controls the battery pack BAT+ to output voltage to the load, and the load receives this voltage through the battery pack output terminal BAT+OUT.

[0062] Please refer to Figure 1 and Figure 2 The driving module 15 includes a first driving unit 151 and a second driving unit 152. The second driving unit 152 includes an input terminal, an output terminal, and a control terminal. One end of the first driving unit 151 is connected to the control module, and the other end of the first driving unit 151 is connected to the control terminal. The input terminal is connected to the second capacitor C2, and the output terminal is connected to the gate of the MOSFET group 16. Based on the control signal and the second voltage released by the second capacitor C2, the second driving unit 152 outputs a third driving signal to the gate of the MOSFET group 16.

[0063] Please refer to Figure 1 and Figure 2The first driving unit 151 includes a first optocoupler OC1 and a second optocoupler OC2. The second driving unit 152 includes a first transistor Q3, a second transistor Q6, a third transistor Q5, and a fourth transistor Q7. The MOSFET group 16 includes a third MOSFET Q5 and a fourth MOSFET Q4. The positive terminal of the input of the first optocoupler OC1 is connected to the control module 14. The negative terminal of the input of the first optocoupler OC1 is grounded. The collector of the output of the first optocoupler OC1 is connected to a second capacitor C2. The emitter of the output of the first optocoupler OC1 is connected to the bases of the first transistor Q3 and the second transistor Q6, respectively. The positive terminal of the input of the second optocoupler OC2 is connected to the control module 14. The negative terminal of the input of the second optocoupler OC2 is grounded. The collector of the output of the second optocoupler OC2 is connected to the second capacitor C2. The emitter of the output of the second optocoupler OC2 is connected to the bases of the third transistor Q8 and the fourth transistor Q7, respectively. The first optocoupler OC1 can be used to control the conduction and cutoff of the first transistor Q3 and the second transistor Q6, and the second optocoupler OC2 can be used to control the conduction and cutoff of the third transistor Q5 and the fourth transistor Q7. The two optocouplers can also be replaced with two dedicated isolation chips, which can achieve the same effect. The totem-pole drive circuit composed of the first transistor Q3, the second transistor Q6, the third transistor Q8, and the fourth transistor Q7 allows the second drive unit 15 to voltage-follow the third drive signal. The input terminals of the second drive unit 152 are the collectors of the first transistor Q3 and the fourth transistor Q7, and the control terminals are the bases of the first transistor Q3, the second transistor Q6, the third transistor Q8, and the fourth transistor Q7. The output terminals of the second drive unit 152 are the emitters of the first transistor Q3 and the second transistor Q6, and also the emitters of the third transistor Q8 and the fourth transistor Q7.

[0064] Please refer to Figure 1 and Figure 2 The driving module 15 includes a seventh resistor and an eighth resistor. One end of the seventh resistor is connected to the collector of the output terminal of the first optocoupler OC1, and the other end of the seventh resistor is grounded. One end of the eighth resistor is connected to the collector of the output terminal of the second optocoupler OC2, and the other end of the eighth resistor is grounded. The driving module 15 also includes a ninth resistor R6 and a tenth resistor R7. The ninth resistor R6 is connected between the gate and source of the third MOSFET, and the tenth resistor R7 is connected between the gate and source of the fourth MOSFET.

[0065] Please refer to Figure 1 and Figure 2The collector of the first transistor Q3 is connected to the second capacitor C2. The emitter of the first transistor Q3 is connected to the gate of the third MOSFET Q5 and the emitter of the second transistor Q6, respectively. The collector of the second transistor Q6 is grounded. The collector of the fourth transistor Q7 is connected to the second capacitor C2. The emitter of the fourth transistor Q7 is connected to the gate of the fourth MOSFET Q4 and the emitter of the third transistor Q8, and the collector of the third transistor Q8 is grounded. Optionally, the drain of the third MOSFET Q5 can also be connected to the drain of the fourth MOSFET Q4. If the drain of the third MOSFET Q5 and the drain of the fourth MOSFET Q4 can also be connected, the MOSFET driving circuit 10 needs to use two floating charge pumps to output voltage to the driving module 15. Thus, the driving module 15 outputs a third driving signal, which controls the conduction and cutoff of the third MOSFET Q5 and the fourth MOSFET Q4.

[0066] The working principle of the MOS transistor driving circuit of the present invention is as follows: When the MOS transistor driving circuit 10 is working, the first signal generation module 12 generates a first signal, and the input pin IN of chip U1 receives the first signal. Based on the first signal, the low-side output pin LO of chip U1 outputs a first driving signal. The gate of the first MOS transistor Q1 in the energy storage module 13 receives the first driving signal. When the first driving signal is high, the first MOS transistor Q1 is turned on. At the same time, the power supply 11 outputs a first voltage, which is received and stored by the first diode D1 and the first capacitor C1. Then, when the first driving signal is low, the first MOS transistor Q1 is turned off. The first capacitor C1 outputs a driving voltage, which is received by the high-side floating absolute voltage pin VB. Based on the driving voltage, the high-side output pin HO of chip U1 outputs a second driving signal. The gate of the second MOS transistor Q2 receives the second driving signal, thereby turning on the second MOS transistor Q2. The first capacitor C1 outputs a first voltage, which is converted into a second voltage by the second MOS transistor Q2 and the second diode D2. The second capacitor C2 receives and stores the second voltage. When the voltage across the second capacitor C2 is lower than that across the first capacitor C1, the first capacitor C1 continuously outputs voltage to the second capacitor C2 through the second diode D2. This process repeats continuously, with the first capacitor C1 constantly replenishing energy to the second capacitor C2. The second capacitor C2 stores this energy, thus isolating the output and ground of the second capacitor C2 from power supply 11 and its ground. Furthermore, the high-side floating offset voltage pin VS of chip U1 can isolate the first capacitor C1 from the gate of the second MOSFET Q2.

[0067] Subsequently, the first control terminal DSG of the first control module 14 outputs a control signal, and the second control terminal CHG of the first control module 14 also outputs a control signal. The first optocoupler OC1 and the second optocoupler OC2 receive this control signal. When the control signal is high, both the first optocoupler OC1 and the second optocoupler OC2 are turned on. At this time, the second capacitor C2 releases a second voltage. This second voltage, through the first optocoupler OC1, turns on the first transistor Q3 and the second transistor Q6, and through the second optocoupler OC2, turns on the third transistor Q8 and the fourth transistor Q7. Based on the control signal and the second voltage, the control module 15 outputs a third drive signal to the gate of the MOSFET group 16. The third drive signal can drive the MOSFET group 16 to turn on, thereby allowing the battery pack BAT+ to output voltage to the load.

[0068] When the load does not require power from the battery pack BAT+, the user can control the first control module 14 to output a low-level control signal. The first optocoupler OC1 and the second optocoupler OC2 receive this low-level control signal, and both the first optocoupler OC1 and the second optocoupler OC2 are turned off. Since the bases of the first transistor Q3 and the second transistor Q6 are both connected to the second capacitor C2 through the first optocoupler OC1, neither the first transistor Q3 nor the second transistor Q6 will conduct. Since the bases of the third transistor Q8 and the fourth transistor Q7 are both connected to the second capacitor C2 through the second optocoupler OC2, neither the third transistor Q8 nor the fourth transistor Q7 will conduct. Therefore, the drive module 15 fails to output the third drive signal, and thus the MOSFET group 16 is not turned on, and the battery pack BAT+ cannot output voltage to the load.

[0069] When the second voltage of the second capacitor C2 is depleted, the drive module 15 fails to output the third drive signal because it outputs the third drive signal based on the second voltage and the control signal. Consequently, the MOSFET group 16 is not turned on, and the battery pack BAT+ cannot output voltage to the load. Subsequently, the chip U1 outputs a high-level first drive signal, turning on the first MOSFET Q1, allowing the power supply 11 to output the first voltage to the energy storage module 13. The energy storage module 13 converts the first voltage into the second voltage, and the second capacitor C2 stores the second voltage. This process is repeated continuously, allowing the battery pack BAT+ to intermittently supply power to the load.

[0070] This invention provides a MOSFET driving circuit 10, which includes an energy storage module 13. Based on a first driving signal output by chip U1, the energy storage module 13 receives and stores a first voltage output by power supply 11. Based on the first and second driving signals output by chip U1, the energy storage module 13 converts the first voltage into a second voltage and stores the second voltage. Based on a control signal output by control module 14 and the second voltage released by energy storage module 13, driving module 15 outputs a third driving signal to the gate of MOSFET group 16. The third driving signal can control the MOSFET group 16 to turn on and off, thereby controlling the battery pack BAT+ output voltage to the load. Because driving module 15 can output the third driving signal based on the control signal and the second voltage, and the third driving signal can control the MOSFET group to turn on and off, this MOSFET driving circuit 10 does not require a dedicated chip to control the high-side MOSFETs, thus reducing the cost of the MOSFET driving circuit 10. It effectively solves the technical problem of high cost of existing drive circuits, and the MOSFET drive circuit 10 controls the output voltage of battery pack BAT+ through MOSFET group 16, making the use of battery pack BAT+ safer.

[0071] The MOSFET driver circuit 10 uses fewer components and has a simpler control scheme, thus offering advantages such as low cost and ease of implementation. This ensures complete disconnection of the positive terminal of battery pack BAT+ compared to previous methods of controlling the negative terminal. Furthermore, the use of discrete components allows for greater flexibility in component selection and simplifies implementation.

[0072] In summary, although the present invention has been disclosed above with reference to preferred embodiments, the above preferred embodiments are not intended to limit the present invention. Those skilled in the art can make various 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 scope defined in the claims.

Claims

1. An energy storage circuit with isolation function, characterized in that, include: The power supply is used to output the first voltage; A first signal generation module is used to generate a first signal; The chip receives the first signal, outputs a first drive signal based on the first signal, and outputs a second drive signal based on the drive voltage output by the energy storage module. as well as The energy storage module receives the first drive signal, receives and stores the first voltage based on the first drive signal, converts the first voltage into a second voltage based on the first drive signal and the second drive signal, and stores the second voltage. The chip includes an input pin and a low-side output pin. The energy storage module includes a first MOSFET and a first capacitor. The input pin is connected to the first signal generation module and is used to receive the first signal. The low-side output pin is connected to the gate of the first MOSFET and is used to output the first drive signal. The source of the first MOSFET is grounded, and the drain of the first MOSFET is connected to the first capacitor. The first capacitor is connected to the power supply. The chip includes a high-side output pin, a high-side floating absolute voltage pin, and a high-side floating offset voltage pin. The energy storage module also includes a second MOSFET and a second capacitor. The source of the second MOSFET is connected to the first capacitor, the drain of the second MOSFET is connected to one end of the second capacitor, the other end of the second capacitor is connected to the first capacitor, and the gate of the second MOSFET is connected to the high-side output pin, which is used to output the second drive signal. The high-side floating absolute voltage pin is connected to one end of the first capacitor and is used to receive the drive voltage. The high-side floating offset voltage pin is connected to the other end of the first capacitor and is used to isolate the first capacitor from the gate of the second MOSFET. The energy storage module further includes a first diode and a second diode. The positive terminal of the first diode is connected to a power source, and the negative terminal of the first diode is connected to the first capacitor. The positive terminal of the second diode is connected to the first capacitor, and the negative terminal of the second diode is connected to the second capacitor.

2. The energy storage circuit with isolation function according to claim 1, characterized in that, When the low-side output pin outputs a high-level first drive signal, the gate of the first MOS transistor receives the high-level first drive signal, the first MOS transistor is turned on, and thus the first capacitor receives and stores the first voltage.

3. The energy storage circuit with isolation function according to claim 1, characterized in that, When the low-side output pin outputs a low-level first drive signal, the gate of the first MOS transistor receives the low-level first drive signal, and the first MOS transistor is turned off. When the first capacitor outputs the driving voltage, the high-side floating absolute voltage pin receives the driving voltage, and the high-side output pin outputs the second driving signal. Based on the second driving signal, the second MOS transistor is turned on, so that the first capacitor outputs the first voltage. The energy storage module converts the first voltage into a second voltage, so that the second capacitor receives and stores the second voltage.

4. The energy storage circuit with isolation function according to claim 1, characterized in that, The energy storage module includes a filtering unit for filtering the first voltage. The filtering unit includes a filtering capacitor, one end of which is connected between the power supply and the positive terminal of the first diode, and the other end of which is grounded.

5. The energy storage circuit with isolation function according to claim 1, characterized in that, The energy storage circuit also includes: The control module is used to output control signals; and, The driving module, based on the control signal and the second voltage released by the energy storage module, outputs a third driving signal to the gate of the MOS transistor group. The third driving signal is used to control the MOS transistor group to turn on and off, thereby the MOS transistor group controls the battery pack to output voltage to the load. The driving module includes a first driving unit and a second driving unit. The second driving unit includes an input terminal, an output terminal, and a control terminal. One end of the first driving unit is connected to the control module, and the other end of the first driving unit is connected to the control terminal. The input terminal is connected to the second capacitor, and the output terminal is connected to the gate of the MOS transistor group. Based on the control signal and the second voltage released by the second capacitor, the second driving unit outputs the third driving signal to the gate of the MOS transistor group and performs voltage following on the third driving signal.

6. The energy storage circuit with isolation function according to claim 5, characterized in that, The first driving unit includes a first optocoupler and a second optocoupler, the second driving unit includes a first transistor, a second transistor, a third transistor, and a fourth transistor, the MOS transistor group includes a third MOS transistor and a fourth MOS transistor, the positive terminal of the first optocoupler input terminal is connected to the control module, the negative terminal of the first optocoupler input terminal is grounded, the collector of the first optocoupler output terminal is connected to the second capacitor, and the emitter of the first optocoupler output terminal is connected to the base of the first transistor and the second transistor respectively; The positive terminal of the second optocoupler input is connected to the control module, the negative terminal of the second optocoupler input is grounded, the collector of the second optocoupler output is connected to the second capacitor, and the emitter of the second optocoupler output is connected to the base of the third transistor and the fourth transistor, respectively. The collector of the first transistor is connected to the second capacitor, the emitter of the first transistor is connected to the gate of the third MOS transistor and the emitter of the second transistor, the collector of the second transistor is grounded, the collector of the fourth transistor is connected to the second capacitor, the emitter of the fourth transistor is connected to the gate of the fourth MOS transistor and the emitter of the third transistor, and the collector of the third transistor is grounded.

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