High-side driving circuit

Abstract

The utility model discloses a high-side driving circuit which comprises an output circuit which comprises a sampling unit and a switch MOS tube, the input end of the sampling unit is used for being connected with a power supply end, the output end of the sampling unit is connected with the input end of the switch MOS tube, and the output end of the switch MOS tube is used for being connected with a load end; the control circuit comprises a control unit and a switch driving unit, the control unit controls on-off of the switch MOS tube through the switch driving unit, in the switch driving unit, a first switch unit is used for enabling the switch MOS tube to be switched on when receiving a first switch signal and enabling the switch MOS tube to be switched off when receiving a second switch signal, and a second switch unit is used for enabling the switch MOS tube to be switched off when receiving a second switch signal. The second switch unit is used for enabling the control end and the input end of the switch MOS tube to be in short circuit when an overcurrent fault occurs; and the feedback circuit is used for enabling the control unit to output a second switching signal when an overcurrent fault occurs at the load end. According to the high-side driving circuit, rapid turn-off of the switch MOS tube can be realized.

Description

Technical Field

[0001] The utility model relates to the technical field of controllers, in particular to a high-side drive circuit. Background Art

[0002] In the existing high-side drive circuit, when the control switch tube is turned off, the parasitic capacitance inside the control switch tube needs to be charged through the current limiting resistor. If the current limiting resistor is too large, the charging process is slow, the turn-off time is long, and the control switch tube is easily damaged. If the current limiting resistor is too small, the current power consumption on the current limiting resistor increases during the opening of the control switch tube. Therefore, how to achieve rapid shutdown of the high-side drive circuit in the event of an overcurrent fault is a technical problem that needs to be solved by those skilled in the art. Utility Model Content

[0003] The utility model provides a high-side drive circuit, which can realize the rapid shutdown of a switch MOS tube, avoid the damage of the switch MOS tube during the shutdown process caused by slow charging, and realize the protection of the circuit.

[0004] In order to achieve the above object, the utility model provides the following technical solutions:

[0005] A high-side driving circuit, comprising:

[0006] An output circuit, the output circuit comprising a sampling unit and a switch MOS tube, the input end of the sampling unit is used to be connected to the power supply end, the output end of the sampling unit is connected to the input end of the switch MOS tube, and the output end of the switch MOS tube is used to be connected to the load end;

[0007] A control circuit, the control circuit comprising a control unit and a switch driving unit, the control unit being used to output a first switch signal and a second switch signal according to a control signal, the control unit controlling the on and off of the switch MOS tube through the switch driving unit, the switch driving unit comprising a first switch unit and a second switch unit, the first switch unit being used to turn on the switch MOS tube when receiving the first switch signal and turn off the switch MOS tube when receiving the second switch signal, the second switch unit being used to short-circuit the control end and the input end of the switch MOS tube when an overcurrent fault occurs at the load end;

[0008] A feedback circuit is connected to both ends of the sampling unit and an input end of the control unit, and is used to enable the control unit to output the second switch signal when an overcurrent fault occurs at the load end.

[0009] Optionally, the sampling unit comprises a sampling resistor, a first end of the sampling resistor is used to be connected to a power supply end, and a second end of the sampling resistor is used to be connected to an input end of the switch MOS tube.

[0010] Optionally, the first switch unit includes a first resistor, a second resistor, a third resistor, a fourth resistor and a first switch tube;

[0011] A first end of the first resistor is connected to the output end of the control unit, a second end of the first resistor is connected to the first end of the second resistor and the control end of the first switch tube, a second end of the second resistor is grounded, a first end of the third resistor is connected to the input end of the switch MOS tube, a second end of the third resistor is connected to the first end of the fourth resistor and the control end of the switch MOS tube, a second end of the fourth resistor is connected to the input end of the first switch tube, and an output end of the first switch tube is grounded;

[0012] When the switch unit receives the first switch signal, the first switch tube is turned on, and the switch MOS tube is turned on;

[0013] When the switch unit receives the second switch signal, the first switch tube is turned off.

[0014] Optionally, the second switch unit includes a fifth resistor, a sixth resistor, a seventh resistor, a second switch tube and a third switch tube;

[0015] The input end of the second switch tube is connected to the input end of the switch MOS tube, the output end of the second switch tube is connected to the control end of the switch MOS tube, the first end of the fifth resistor is connected to the input end of the switch MOS tube, the second end of the fifth resistor is connected to the first end of the sixth resistor and the first end of the seventh resistor, the second end of the sixth resistor is connected to the control end of the switch MOS tube, the second end of the seventh resistor is connected to the input end of the third switch tube, the output end of the third switch tube is grounded, and the control end of the third switch tube is connected to the input end of the first switch tube;

[0016] When an overcurrent fault occurs at the load end, the second switch tube and the third switch tube are turned on.

[0017] Optionally, the feedback circuit includes a fourth switch tube, a fifth switch tube, an eighth resistor, a ninth resistor, a tenth resistor and an eleventh resistor;

[0018] The first end of the eighth resistor is connected to the second end of the sampling resistor, the second end of the eighth resistor is connected to the control end of the fourth switch tube, the input end of the fourth switch tube is connected to the first end of the sampling resistor, the output end of the fourth switch tube is connected to the first end of the ninth resistor, the second end of the ninth resistor is connected to the control end of the fifth switch tube and the first end of the tenth resistor, the second end of the tenth resistor is grounded, the input end of the fifth switch tube is connected to the feedback power supply through the eleventh resistor and is connected to the input end of the control unit, and the output end of the fifth switch tube is grounded;

[0019] When an overcurrent fault occurs at the load end, the fourth switch tube and the fifth switch tube are turned on.

[0020] Optionally, the voltage of the feedback power supply is +5V.

[0021] Optionally, the control unit includes an AND gate;

[0022] The first input end of the AND gate is connected to the output control end for receiving the control signal, the second input end of the AND gate is connected to the input end of the fifth switch tube, and the output end of the AND gate is connected to the first end of the first resistor.

[0023] Optionally, the control unit further includes a twelfth resistor, a first end of the twelfth resistor is connected to the first end of the first resistor, and a second end of the twelfth resistor is connected to the first input end of the AND gate.

[0024] Optionally, the first switch tube, the second switch tube, the third switch tube, the fourth switch tube and the fifth switch tube are triodes.

[0025] Optionally, the first switch signal is at a high level, and the second switch signal is at a low level.

[0026] The utility model provides a high-side drive circuit, comprising an output circuit, a control circuit and a feedback circuit. The output circuit is connected to a power supply end and a resistor end through a sampling unit and a switch MOS tube. A control unit in the control circuit can control the on-off of the switch MOS tube through the switch drive unit to control the on-off between the power supply end and the load end. When the control unit outputs a first switch signal, a first switch unit of the switch drive unit can turn on the switch MOS tube so that the power supply end and the load end are connected. When the control unit outputs a second switch signal, the first switch unit can turn off the switch MOS tube. Since the feedback circuit is connected to both ends of the sampling unit and the control unit, when an overcurrent fault occurs at the load end, the feedback circuit can make the control unit output the second switch signal according to the state of the sampling unit so that the voltage difference between the input end and the control end of the switch MOS tube is equal to 0, and the second switch unit of the switch drive unit is turned on so that the control end and the input end of the switch MOS tube are short-circuited. In the process of turning off the switch MOS tube, the internal parasitic capacitance of the switch MOS tube can be quickly charged, thereby realizing the rapid turning off of the switch MOS tube, avoiding the damage of the switch MOS tube during the turning off process due to slow charging, and realizing the protection of the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic diagram of the structure of a high-side drive circuit provided in the related art;

[0028] Figure 2 A schematic diagram of the structure of a high-side drive circuit provided by an embodiment of the utility model;

[0029] Figure 3 A schematic diagram of the structure of another high-side drive circuit provided in an embodiment of the utility model.

[0030] icon:

[0031] 1-output circuit; 11-sampling unit; 2-control circuit; 21-control unit; 22-switch driving unit; 3-feedback circuit. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0033] A high-side drive circuit structure in the related art can be as follows: Figure 1As shown, in the high-side drive circuit, the power supply terminal VBAT, the load terminal OUT and the output control terminal OUT_CTR, the output control terminal OUT_CTR can be connected to the control chip, and is used to control the third MOS tube M3 in the high-side drive circuit to be turned on and off. When the output control terminal OUT_CTR inputs a high level, the third MOS tube M3 is turned on, the power supply terminal VBAT and the load terminal OUT are turned on, and under the action of the voltage difference across the current limiting resistor R02, the first MOS tube M1 and the second MOS tube M2 are turned on. When an overcurrent fault occurs, a voltage difference is generated across the signal acquisition resistor R01, the fifth MOS tube M5 is turned on, the fourth MOS tube M4 is turned on, and the sixth MOS tube M6 is turned on under the action of the voltage difference, and the fifth MOS tube M5 is maintained on. At this time, the third MOS tube M3 is turned off, and the second MOS tube M2 is turned off, so that the power supply terminal VBAT and the load terminal OUT are turned off, so as to achieve the overcurrent protection capability. In the above technology, during the shutdown process of the second MOS tube M2, because the internal parasitic capacitance of the second MOS tube M2 needs to be charged through the current limiting resistor R02, if the current limiting resistor R02 is too large, the charging process is slow, the shutdown time is long, and the MOS tube is easily damaged. If the current limiting resistor is too small, the current power consumption on the current limiting resistor R2 increases during the opening process of the second MOS tube M2 and the third MOS tube M3. Therefore, how to achieve rapid shutdown of the high-side drive circuit in the event of an overcurrent fault is a technical problem that needs to be solved by those skilled in the art.

[0034] In view of the above technical problems, the utility model provides a high-side drive circuit, such as Figure 2 As shown, including:

[0035] Output circuit 1, the output circuit 1 includes a sampling unit 11 and a switch MOS tube M0, the input end of the sampling unit 11 is used to connect to the power supply end VBAT1, the output end of the sampling unit 11 is connected to the input end of the switch MOS tube M0, and the output end of the switch MOS tube M0 is used to connect to the load end OUT1;

[0036] A control circuit 2, the control circuit 2 includes a control unit 21 and a switch driving unit 22, the control unit 21 is used to output a first switch signal and a second switch signal according to a control signal, the control unit 21 controls the on and off of the switch MOS tube M0 through the switch driving unit 22, the switch driving unit 22 includes a first switch unit and a second switch unit, the first switch unit is used to turn on the switch MOS tube M0 when receiving the first switch signal and turn off the switch MOS tube M0 when receiving the second switch signal, and the second switch unit is used to short-circuit the control end and the input end of the switch MOS tube M0 when an overcurrent fault occurs at the load end OUT1;

[0037] The feedback circuit 3 is connected to both ends of the sampling unit 11 and the input end of the control unit 21 , and is used to enable the control unit 21 to output a second switch signal when an overcurrent fault occurs at the load end OUT1 .

[0038] The high-side drive circuit provided in the above-mentioned utility model embodiment includes an output circuit 1, a control circuit 2 and a feedback circuit 3. The output circuit 1 is connected to the power supply terminal VBAT1 and the resistance terminal through the sampling unit 11 and the switch MOS tube M0. The control unit 21 in the control circuit 2 can control the on-off of the switch MOS tube M0 through the switch driving unit 22 to control the on-off between the power supply terminal VBAT1 and the load terminal OUT1. When the control unit 21 outputs a first switch signal, the first switch unit of the switch driving unit 22 can turn on the switch MOS tube M0, so that the power supply terminal VBAT1 and the load terminal OUT1 are connected, and when the control unit 21 outputs a second switch signal, the first switch unit can turn on the switch MOS tube M0. 0 is turned off. Since the feedback circuit 3 is connected to both ends of the sampling unit 11 and the control unit 21, when an overcurrent fault occurs at the load end OUT1, the feedback circuit 3 can make the control unit 21 output a second switching signal according to the state of the sampling unit 11, so that the voltage difference between the input end and the control end of the switch MOS tube M0 is equal to 0, and the second switch unit of the switch driving unit 22 is turned on to short-circuit the control end and the input end of the switch MOS tube M0. In the process of turning off the switch MOS tube M0, the internal parasitic capacitance of the switch MOS tube M0 can be quickly charged, thereby realizing the rapid turning off of the switch MOS tube M0, avoiding damage to the switch MOS tube M0 during the turning off process due to slow charging, and realizing the protection of the circuit.

[0039] Specifically, the switch MOS tube M0 may be a PMOS tube.

[0040] In the embodiment of the utility model, Figure 3 As shown, the sampling unit 11 may include a sampling resistor R0, a first end of the sampling resistor R0 is used to be connected to the power supply terminal VBAT1, and a second end of the sampling resistor R0 is used to be connected to the input end of the switch MOS tube M0. When an overcurrent fault occurs at the load terminal OUT1, the current flowing through the sampling resistor R0 increases, and the large current forms a voltage difference through the sampling resistor R0. The voltage difference on the sampling resistor R0 can trigger the feedback circuit 3 to output a feedback signal. After receiving the feedback signal, the control unit 21 can output a second switch signal to turn off the switch MOS tube M0.

[0041] In the embodiment of the utility model, Figure 3As shown, the first switch unit may include a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4 and a first switch tube Q1; wherein, a first end of the first resistor R1 is connected to an output end of the control unit 21, a second end of the first resistor R1 is connected to a first end of the second resistor R2 and a control end of the first switch tube Q1, a second end of the second resistor R2 is grounded, a first end of the third resistor R3 is connected to an input end of the switch MOS tube M0, a second end of the third resistor R3 is connected to a first end of the fourth resistor R4 and a control end of the switch MOS tube M0, a second end of the fourth resistor R4 is connected to an input end of the first switch tube Q1, and an output end of the first switch tube Q1 is grounded; when the switch unit receives a first switch signal, the first switch tube Q1 is turned on, and the switch MOS tube M0 is turned on; when the switch unit receives a second switch signal, the first switch tube Q1 is turned off.

[0042] Specifically, the first switch signal may be a high-level signal, the second switch signal may be a low-level signal, and the first switch tube Q1 may be a triode.

[0043] In the above-mentioned high-side drive circuit, when the output end of the control unit 21 outputs a high-level signal, the voltage division of the first resistor R1 and the second resistor R2 can make the first switch tube Q1 fully open, the input end and the output end of the first switch tube Q1 are turned on, the branch where the third resistor R3 and the fourth resistor R4 are located is turned on, and the voltage division requirement of the third resistor R3 and the fourth resistor R4 can be greater than the turn-on threshold of the switch MOS tube M0, thereby making the switch MOS tube M0 turned on, and the power supply end VBAT1 of the high-side drive circuit is connected to the load end OUT1. When the output end of the control unit 21 outputs a low-level signal, the first switch tube Q1 cannot be turned on, the branch where the third resistor R3 and the fourth resistor R4 are located is not turned on, and the power supply end VBAT1 of the high-side drive circuit cannot be connected to the load end OUT1.

[0044] In the embodiment of the utility model, Figure 3 As shown, the second switch unit may include a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a second switch tube Q2 and a third switch tube Q3; wherein, the input end of the second switch tube Q2 is connected to the input end of the switch MOS tube M0, the output end of the second switch tube Q2 is connected to the control end of the switch MOS tube M0, the first end of the fifth resistor R5 is connected to the input end of the switch MOS tube M0, the second end of the fifth resistor R5 is connected to the first end of the sixth resistor R6 and the first end of the seventh resistor R7, the second end of the sixth resistor R6 is connected to the control end of the switch MOS tube M0, the second end of the seventh resistor R7 is connected to the input end of the third switch tube Q3, the output end of the third switch tube Q3 is grounded, and the control end of the third switch tube Q3 is connected to the input end of the first switch tube Q1; when an overcurrent fault occurs at the load end, the second switch tube Q2 and the third switch tube Q3 are turned on.

[0045] Specifically, the second switch tube Q2 and the third switch tube Q3 may be triodes.

[0046] In the above-mentioned high-side driving circuit, when the output end of the control unit 21 outputs a high level, the first switch tube Q1 is turned on, the switch MOS tube M0 is turned on, and the high-side driving circuit is driven normally. At this time, the control end of the third switch tube Q3 receives a low-level signal, the third switch tube Q3 is not turned on, and the second switch tube Q2 is not turned on. When an overcurrent fault occurs, a large current forms a voltage difference through the sampling resistor R0, and the feedback circuit 3 can make the control unit 21 output a low level, then the first switch tube Q1 is turned off, and no current passes through the fourth resistor R4. The voltage difference between the input end and the control end of the switch MOS tube M0 is 0, and the control end of the third switch tube Q3 receives The voltage of the third resistor R3 and the fourth resistor R4 ensures that the third switch tube Q3 is turned on, the branch where the fifth resistor R5 and the seventh resistor R7 are located is turned on, and the current forms a voltage difference through the fifth resistor R5, so that the second switch tube Q2 is turned on, and the control end and the input end of the switch MOS tube M0 are short-circuited. When the switch MOS tube M0 is turned off, the third resistor R3 and the fourth resistor R4 are short-circuited to quickly charge the parasitic capacitance inside the switch MOS tube M0, so as to realize the fast shutdown of the switch MOS tube M0, avoid slow charging, and damage to the switch MOS tube M0 during the shutdown process, so as to achieve the function of over-current fast shutdown protection.

[0047] In the embodiment of the utility model, Figure 3 As shown, the feedback circuit 3 may include a fourth switch tube Q4, a fifth switch tube Q5, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10 and an eleventh resistor R11; the first end of the eighth resistor R8 is connected to the second end of the sampling resistor R0, the second end of the eighth resistor R8 is connected to the control end of the fourth switch tube Q4, the input end of the fourth switch tube Q4 is connected to the first end of the sampling resistor R0, the output end of the fourth switch tube Q4 is connected to the first end of the ninth resistor R9, the second end of the ninth resistor R9 is connected to the control end of the fifth switch tube Q5 and the first end of the tenth resistor R10, the second end of the tenth resistor R10 is grounded, the input end of the fifth switch tube Q5 is connected to the feedback power supply V1 through the eleventh resistor R11, and is connected to the input end of the control unit 21, the output end of the fifth switch tube Q5 is grounded, and the second end of the tenth resistor R10 is grounded; when an overcurrent fault occurs at the load end OUT1, the fourth switch tube Q4 and the fifth switch tube Q5 are turned on. Specifically, the voltage of the feedback power supply V1 may be +5V, and the fourth switch tube Q4 and the fifth switch tube Q5 may be triodes.

[0048] In the above-mentioned high-side drive circuit, when the switch MOS tube M0 is not turned on and no overcurrent fault occurs, the fourth switch tube Q4 and the fifth switch tube Q5 are not turned on, and under the pull-up effect and current limiting effect of the eleventh resistor R11, the feedback circuit 3 outputs a high-level signal, and the control unit 21 can output the first switch signal or the second switch signal according to the control signal and the signal output by the feedback circuit 3. When the switch MOS tube M0 is turned on and an overcurrent fault occurs, the voltage drop formed by the overcurrent can make the fourth switch tube Q4 turn on, and the voltage division of the ninth resistor R9 and the tenth resistor R10 can ensure that the fifth switch tube Q5 is turned on. At this time, the feedback circuit 3 can output a low-level signal, and the control unit 21 can output the second switch signal according to the control signal and the signal output by the feedback circuit 3, so that the first switch tube Q1 is turned off.

[0049] In the embodiment of the utility model, Figure 3 As shown, the control unit 21 may include an AND gate A; wherein the first input end of the AND gate A is connected to the output control end OUT_CTR1 for receiving a control signal, the second input end of the AND gate A is connected to the input end of the fifth switch tube Q5, and the output end of the AND gate A is connected to the first end of the first resistor R1. Specifically, the output control end OUT_CTR1 may be connected to a control chip, such as a single-chip microcomputer, and the signal transmitted by the control chip to the output control end OUT_CTR1 may control the on and off of the switch MOS tube M0.

[0050] In the above-mentioned high-side driving circuit, when the circuit connected to the load terminal OUT1 is normal, the feedback circuit 3 outputs a high-level signal, and the control signal sent by the control chip received by the output control back end can be a high-level signal or a low-level signal; if the switch MOS tube M0 needs to be in an off state, the control chip can transmit a low-level signal to the output control terminal OUT_CTR1, so that the output terminal of the AND gate A outputs a low-level signal, so that the first switch tube Q1 is turned off, and then the switch MOS tube M0 is turned off; if the open-tube MOS tube needs to be in an on state, the control chip can transmit a high-level signal to the output control terminal OUT_CTR1, so that the AND gate A outputs a low-level signal, so that the first switch tube Q1 is turned off, and then the switch MOS tube M0 is turned off; The output terminal of the gate A outputs a high-level signal, the first switch tube Q1 is turned on, and then the switch MOS tube M0 is turned on. If an overcurrent fault occurs at this time, the large current causes a pressure difference to turn on the fourth switch tube Q4, and then the fifth switch tube Q5 is turned on. The feedback circuit 3 outputs a low-level signal, and then the output terminal of the AND gate A outputs a low-level signal, so that the first switch tube Q1 is turned off. At this time, the third switch tube Q3 is turned on, the sixth switch tube is turned on, the control end and the input end of the switch MOS tube M0 are short-circuited, and the large current quickly charges the parasitic capacitance inside the switch MOS tube M0. The switch MOS tube M0 can be quickly turned off, thereby achieving a fast shutdown protection function in the event of an overcurrent fault.

[0051] Specifically, the control unit 21 may further include a twelfth resistor R12 , wherein a first end of the twelfth resistor R12 is connected to a first end of the first resistor R1 , and a second end of the twelfth resistor R12 is connected to a first input end of the AND gate A.

[0052] In the above high-side drive circuit, when the signal of the output control terminal OUT_CTR1 is a high-level signal and the output terminal of the AND gate A is a high-level signal, the output control terminal OUT_CTR1 can be maintained at a high level through the feedback of the twelfth resistor R12. At this time, the pin connected to the control chip and the output control terminal OUT_CTR1 can be configured as an input to detect the high and low levels of the output control terminal OUT_CTR1 as a flag bit of an overcurrent fault. The voltage difference between the control terminal and the input terminal of the third switch tube Q3 is less than 0, the third switch tube Q3 is turned on, the high-side drive circuit is driven normally, and the second The switch tube Q2 is not conducting, and if an overcurrent fault occurs, the feedback circuit 3 outputs a low-level signal, and the output end of the AND gate A outputs a low-level signal. Through the feedback effect of the twelfth resistor R12, the control chip can detect that the output control end OUT_CTR1 is a low-level signal, that is, a short-circuit fault occurs in the circuit connected to the load end OUT1. At this time, the fault can be latched to avoid the switch MOS tube M0 from being continuously turned on and off during the continuous short circuit, working in the SOA area for a long time and burning. The fault can only be cured when the control chip outputs a high-level signal to the output control end OUT_CTR1 again. In the above high-side drive circuit, the output control end OUT_CTR1 can enable one pin of the control chip to realize two functions, which can be used as an enable drive for the start of the high side and as an input flag symbol for the occurrence of a high-side fault, saving the pins of the control chip.

[0053] The following is a detailed description of the embodiment of the utility model in conjunction with the overall circuit diagram. Figure 3 As shown, it is a complete circuit diagram of a high-side drive circuit provided by an embodiment of the utility model. The overall circuit diagram is simple and can be implemented by MOS tubes and triodes. The power supply terminal VBAT1 of the high-side drive circuit can be connected to the power supply, the load terminal OUT1 can be connected to the load circuit, and the output control terminal OUT_CTR1 can be connected to the control chip, and the on and off of the high-side drive circuit can be controlled by the control chip.

[0054] When the output control terminal OUT_CTR1 receives a low level signal, the first input terminal of the AND gate A receives a low level signal, the second input terminal of the AND gate A receives a high level signal, the output terminal of the AND gate A outputs a low level signal, the first switch tube Q1 to the fifth switch tube Q5 and the switch MOS tube M0 are all turned off, and the high-side drive circuit does not work.

[0055] When the output control terminal OUT_CTR1 receives a high-level signal, the first input terminal and the second input terminal of the AND gate A both receive high-level signals, and the output terminal of the AND gate A outputs a high-level signal, the first switch tube Q1 is turned on, and then the switch MOS tube M0 is turned on, the high-side drive circuit is driven normally, and the second switch tube Q2 to the fourth switch tube Q4 are not turned on. If an overcurrent fault occurs, the voltage drop formed by the overcurrent at both ends of the sampling resistor R0 can turn on the fourth switch tube Q4, and then the fifth switch tube Q5 is turned on, and the second input terminal of the AND gate A receives a low-level signal, which causes the output terminal of the AND gate A to output a low-level signal, and then the first switch tube Q1 is turned off, the voltage difference between the control terminal and the input terminal of the switch MOS tube M0 is equal to 0, and the third switch tube Q3 is turned on, the second switch tube Q2 is turned on, and the control terminal and the input terminal of the switch MOS tube M0 are short-circuited. During the shutdown process of the switch MOS tube M0, the current can quickly charge the internal parasitic capacitance of the switch MOS, thereby realizing the rapid shutdown of the switch MOS, avoiding the problem of slow charging and damage to the switch MOS tube M0 during the shutdown process.

[0056] Furthermore, during the normal driving process of the high-side drive circuit, the output control terminal OUT_CTR1 of the high-side drive circuit can be maintained at a high level through the feedback of the twelfth resistor R12. At this time, the control chip can detect whether an overcurrent fault occurs by detecting the high / low level of the output control terminal OUT_CTR1. When an overcurrent fault occurs, the signal of the output control terminal OUT_CTR1 becomes a low level through the feedback of the twelfth resistor R12. After the control chip detects the low-level signal, it is determined that a short-circuit fault occurs, and the fault can be latched. When the control chip sends a high-level signal to the output control terminal OUT_CTR1, the high-side drive circuit can resume normal operation.

[0057] Obviously, those skilled in the art can make various changes and modifications to the embodiments of the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A high-side driver circuit, It is characterized in that include: An output circuit, the output circuit comprising a sampling unit and a switch MOS tube, the input end of the sampling unit is used to be connected to the power supply end, the output end of the sampling unit is connected to the input end of the switch MOS tube, and the output end of the switch MOS tube is used to be connected to the load end; A control circuit, the control circuit comprising a control unit and a switch driving unit, the control unit being used to output a first switch signal and a second switch signal according to a control signal, the control unit controlling the on and off of the switch MOS tube through the switch driving unit, the switch driving unit comprising a first switch unit and a second switch unit, the first switch unit being used to turn on the switch MOS tube when receiving the first switch signal and turn off the switch MOS tube when receiving the second switch signal, the second switch unit being used to short-circuit the control end and the input end of the switch MOS tube when an overcurrent fault occurs at the load end; A feedback circuit is connected to both ends of the sampling unit and an input end of the control unit, and is used to enable the control unit to output the second switch signal when an overcurrent fault occurs at the load end.

2. The high-side driver circuit according to claim 1, It is characterized in that The sampling unit comprises a sampling resistor, a first end of the sampling resistor is used to be connected to a power supply end, and a second end of the sampling resistor is used to be connected to an input end of the switch MOS tube.

3. The high-side driver circuit according to claim 2, It is characterized in that The first switch unit includes a first resistor, a second resistor, a third resistor, a fourth resistor and a first switch tube; A first end of the first resistor is connected to the output end of the control unit, a second end of the first resistor is connected to the first end of the second resistor and the control end of the first switch tube, a second end of the second resistor is grounded, a first end of the third resistor is connected to the input end of the switch MOS tube, a second end of the third resistor is connected to the first end of the fourth resistor and the control end of the switch MOS tube, a second end of the fourth resistor is connected to the input end of the first switch tube, and an output end of the first switch tube is grounded; When the switch unit receives the first switch signal, the first switch tube is turned on, and the switch MOS tube is turned on; When the switch unit receives the second switch signal, the first switch tube is turned off.

4. The high-side driver circuit according to claim 3, It is characterized in that The second switch unit includes a fifth resistor, a sixth resistor, a seventh resistor, a second switch tube and a third switch tube; The input end of the second switch tube is connected to the input end of the switch MOS tube, the output end of the second switch tube is connected to the control end of the switch MOS tube, the first end of the fifth resistor is connected to the input end of the switch MOS tube, the second end of the fifth resistor is connected to the first end of the sixth resistor and the first end of the seventh resistor, the second end of the sixth resistor is connected to the control end of the switch MOS tube, the second end of the seventh resistor is connected to the input end of the third switch tube, the output end of the third switch tube is grounded, and the control end of the third switch tube is connected to the input end of the first switch tube; When an overcurrent fault occurs at the load end, the second switch tube and the third switch tube are turned on.

5. The high-side driver circuit according to claim 4, It is characterized in that The feedback circuit includes a fourth switch tube, a fifth switch tube, an eighth resistor, a ninth resistor, a tenth resistor and an eleventh resistor; The first end of the eighth resistor is connected to the second end of the sampling resistor, the second end of the eighth resistor is connected to the control end of the fourth switch tube, the input end of the fourth switch tube is connected to the first end of the sampling resistor, the output end of the fourth switch tube is connected to the first end of the ninth resistor, the second end of the ninth resistor is connected to the control end of the fifth switch tube and the first end of the tenth resistor, the second end of the tenth resistor is grounded, the input end of the fifth switch tube is connected to the feedback power supply through the eleventh resistor and is connected to the input end of the control unit, and the output end of the fifth switch tube is grounded; When an overcurrent fault occurs at the load end, the fourth switch tube and the fifth switch tube are turned on.

6. The high-side driver circuit according to claim 5, It is characterized in that The voltage of the feedback power supply is +5V.

7. The high-side driver circuit according to claim 5, It is characterized in that The control unit comprises an AND gate; The first input end of the AND gate is connected to the output control end for receiving the control signal, the second input end of the AND gate is connected to the input end of the fifth switch tube, and the output end of the AND gate is connected to the first end of the first resistor.

8. The high-side driver circuit according to claim 7, It is characterized in that The control unit further includes a twelfth resistor, a first end of the twelfth resistor is connected to the first end of the first resistor, and a second end of the twelfth resistor is connected to the first input end of the AND gate.

9. The high-side driver circuit according to claim 8, It is characterized in that The first switch tube, the second switch tube, the third switch tube, the fourth switch tube and the fifth switch tube are triodes.

10. The high-side driver circuit according to any one of claims 1 to 9, It is characterized in that The first switch signal is at a high level, and the second switch signal is at a low level.

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