A protection circuit for suppressing transient overshoot

Abstract

This invention provides a protection circuit for suppressing transient overshoot, comprising a signal processing module, an adjustment module, and a control module connected in sequence. The input terminal of the signal processing module and the first input terminal of the control module are both connected to a first external signal voltage VS1. The first reference terminal of the adjustment module and the second input terminal of the control module are both connected to an internal signal voltage VS2. The signal processing module is configured to output a first voltage V1 to the adjustment module based on the first external signal voltage VS1 when a power circuit fault occurs, thereby reducing the internal signal voltage VS2. The control module is configured to output a control voltage to shut down the power circuit when the first external signal voltage VS1 is higher than a threshold voltage. The control module is further configured to output a corresponding control voltage to the power circuit based on the first external signal voltage VS1 and the internal signal voltage VS2 when the power circuit returns to normal, thereby reducing transient overshoot during the process of the power circuit recovering from a fault state to a normal state.

Description

Technical Field

[0001] This invention relates to the field of circuit protection technology, and specifically to a protection circuit for suppressing transient overshoot. Background Technology

[0002] Existing power supply circuits typically include a semiconductor integrated circuit chip and a power circuit. The semiconductor integrated circuit chip samples external signals in the power circuit. When the external signal reaches a set threshold voltage, the circuit is determined to be in a fault state. At this time, the semiconductor integrated circuit chip outputs a control signal to shut down the power circuit, thus protecting the circuit. When the fault is cleared and the circuit returns to normal, the external signal voltage drops back to normal levels, and the semiconductor integrated circuit chip then restarts control of the power circuit to resume operation.

[0003] However, during the process of a circuit recovering from a faulty state to a normal state, some control signals (such as compensation signals) inside the semiconductor integrated circuit chip may still remain at the normal voltage level before the fault. Since the output current or voltage at the circuit output is usually positively correlated with the voltage of these internal control signals, when the chip restarts the power circuit, it will directly drive the power circuit to work based on the internal signal voltage that has not yet been updated. This can easily lead to transient overshoot at the circuit output, thereby affecting the system stability and safety. Summary of the Invention

[0004] The purpose of this invention is to solve the problem of transient overshoot caused by the failure of internal signals to adjust in time during the recovery process from a fault state to a normal state in existing power circuits.

[0005] According to a first aspect of the present invention, a protection circuit for suppressing transient overshoot is provided, the protection circuit being used to protect a power circuit, the protection circuit comprising a signal processing module, an adjustment module, and a control module connected in sequence;

[0006] The input terminal of the signal processing module and the first input terminal of the control module are both connected to a first external signal voltage VS1; the first reference terminal of the adjustment module and the second input terminal of the control module are both connected to an internal signal voltage VS2.

[0007] The first reference terminal of the signal processing module is connected to the chip input voltage VIN, the second reference terminal of the signal processing module is grounded, the output terminal of the signal processing module is connected to the input terminal of the adjustment module, and the signal processing module is configured to output a first voltage V1 to the adjustment module according to the first external signal voltage VS1 when the power circuit fails, so that the internal signal voltage VS2 is reduced.

[0008] The output terminal of the control module is connected to the power circuit and is used to output a control voltage to turn off the power circuit when the first external signal voltage VS1 is higher than the threshold voltage. The control module is also configured to output a corresponding control voltage to the power circuit according to the first external signal voltage VS1 and the internal signal voltage VS2 when the power circuit returns to normal, so as to reduce the transient overshoot during the process of the power circuit recovering from the fault state to the normal state.

[0009] In one possible implementation, the signal processing module includes:

[0010] The sampling unit has its input terminal serving as the input terminal of the signal processing module, its first reference terminal serving as the first reference terminal of the signal processing module, and its second reference terminal serving as the second reference terminal of the signal processing module.

[0011] The first comparison unit has its first terminal connected to the sampling unit to receive the second voltage V2 output by the sampling unit, and its second terminal is grounded.

[0012] A conversion unit has its input terminal connected to the first comparison unit to receive the third voltage V3 output by the first comparison unit. The output terminal of the conversion unit serves as the output terminal of the signal processing module. The first reference terminal of the conversion unit is connected to the sampling unit to receive the second voltage V2. The second reference terminal of the conversion unit is grounded, and the third reference terminal of the conversion unit is connected to the internal signal voltage VS2.

[0013] In one possible implementation, in the sampling unit, the chip input voltage VIN is grounded sequentially through a first resistor R1 and a first switch M1; the chip input voltage VIN is also grounded sequentially through a second resistor R2 and a second switch M2; the chip input voltage VIN is also grounded sequentially through a third switch M3 and a fourth switch M4; and the chip input voltage VIN is also grounded sequentially through a fifth switch M5 and a sixth switch M6.

[0014] The control terminal of the first switch M1 serves as the input terminal of the sampling unit. The control terminal of the second switch M2 is connected to the current output terminal of the fifth switch M5. The control terminal of the third switch M3 is connected to the current input terminal of the second switch M2. The control terminal of the fourth switch M4 is connected to the current input terminal of the fourth switch M4. The control terminal of the fifth switch M5 is connected to the current input terminal of the first switch M1. The control terminal of the sixth switch M6 is connected to the control terminal of the fourth switch M4.

[0015] In one possible implementation, in the sampling unit, the chip input voltage VIN is also grounded sequentially through the seventh switch M7, the eighth switch M8, the ninth switch M9, and the tenth switch M10; the chip input voltage VIN is also grounded sequentially through the eleventh switch M11 and the twelfth switch M12; and the chip input voltage VIN is also grounded sequentially through the third resistor R3 and the thirteenth switch M13.

[0016] The control terminal of the seventh switch M7 is connected to the control terminal of the eleventh switch M11, the control terminal of the eighth switch M8 is connected to the current output terminal of the eighth switch M8, the control terminal of the ninth switch M9 is connected to the current output terminal of the fifth switch M5, the control terminal of the tenth switch M10 is connected to the control terminal of the twelfth switch M12, the control terminal of the eleventh switch M11 is connected to the current output terminal of the eleventh switch M11, the control terminal of the twelfth switch M12 is connected to the control terminal of the thirteenth switch M13, and the control terminal of the thirteenth switch M13 is connected to the current input terminal of the thirteenth switch M13.

[0017] The voltage at the current output terminal of the seventh switch M7 is the second voltage V2.

[0018] In one possible implementation, in the first comparison unit, the second voltage V2 is grounded sequentially through a fourth resistor R4 and a fifth resistor R5; the second voltage V2 is also grounded sequentially through a sixth resistor R6, a first transistor Q1, and a fourteenth switch M14; the second voltage V2 is also grounded sequentially through a sixth resistor R6, a seventh resistor R7, a second transistor Q2, and a fifteenth switch M15; the second voltage V2 is also grounded sequentially through a sixteenth switch M16 and a seventeenth switch M17; and the second voltage V2 is also grounded sequentially through an eighteenth switch M18 and a nineteenth switch M19.

[0019] The bases of the first transistor Q1 and the second transistor Q2 are both connected between the fourth resistor R4 and the fifth resistor R5; the control terminal of the fourteenth switch M14 is connected to the current input terminal of the fourteenth switch M14, and the control terminal of the nineteenth switch M19 is connected to the control terminal of the fourteenth switch M14; the control terminal of the fifteenth switch M15 is connected to the current input terminal of the fifteenth switch M15, and the control terminal of the seventeenth switch M17 is connected to the control terminal of the fifteenth switch M15; the control terminal of the sixteenth switch M16 is connected to the current output terminal of the sixteenth switch M16, and the control terminal of the eighteenth switch M18 is connected to the control terminal of the sixteenth switch M16;

[0020] The current output voltage of the eighteenth switch M18 is the third voltage V3.

[0021] In one possible implementation, the ratio of the number of the first transistor Q1 to the number of the second transistor Q2 is 1:N.

[0022] In one possible implementation, the adjustment module further includes a second reference terminal, which is grounded.

[0023] In one possible implementation, the conversion unit includes a first inverter A1, a twentieth switch M20, a twenty-first switch M21, a twenty-second switch M22, and a twenty-third switch M23;

[0024] The input terminal of the first inverter A1 serves as the input terminal of the conversion unit, the first reference terminal of the first inverter A1 serves as the first reference terminal of the conversion unit, and the second reference terminal of the first inverter A1 serves as the second reference terminal of the conversion unit.

[0025] The current input terminal of the twentieth switch M20 is connected to the internal signal voltage VS2, and the current output terminal is grounded through the eleventh switch M21; the current input terminal of the twelfth switch M22 is connected to the current input terminal of the twentieth switch M20, and the current output terminal is grounded through the thirteenth switch M23; the control terminal of the twentieth switch M20 is connected to the current output terminal of the twelfth switch M22, and the control terminal of the twelfth switch M22 is connected to the current output terminal of the twentieth switch M20; the control terminal of the eleventh switch M21 is connected to the input terminal of the first inverter A1, and the control terminal of the thirteenth switch M23 is connected to the output terminal of the first inverter A1.

[0026] In one possible implementation, the conversion unit further includes:

[0027] The second inverter A2 has its input terminal connected to the current output terminal of the twelfth switching transistor M22. The first reference terminal of the second inverter A2 serves as the third reference terminal of the conversion unit, and the second reference terminal of the second inverter A2 serves as the second reference terminal of the conversion unit.

[0028] The third inverter A3 has its input terminal connected to the output terminal of the second inverter A2. The output terminal of the third inverter A3 outputs the first voltage V1. The first reference terminal of the third inverter A3 is connected to the first reference terminal of the second inverter A2, and the second reference terminal of the third inverter A3 is connected to the second reference terminal of the second inverter A2.

[0029] In one possible implementation, in the adjustment module, the internal signal voltage VS2 is grounded sequentially through the 24th switch M24, the current source BB, and the first voltage source; the control terminal of the 24th switch M24 is connected to the output terminal of the third inverter A3.

[0030] In one possible implementation, the adjustment module further includes a second reference terminal, and the conversion unit further includes a fourth reference terminal. Both the fourth reference terminal of the conversion unit and the second reference terminal of the adjustment module are connected to a second external signal voltage VA. The second external signal voltage VA is positively correlated with the output current or output voltage of the power circuit.

[0031] The adjustment module is configured to adjust the internal signal voltage VS2 during the process of the power circuit returning from a fault state to a normal state, so that the internal signal voltage VS2 and the second external signal voltage VA maintain a preset voltage difference.

[0032] In one possible implementation, the conversion unit includes a 25th switch M25, a 26th switch M26, a 27th switch M27, a 28th switch M28, and a fourth inverter A4;

[0033] The input terminal of the fourth inverter A4 serves as the input terminal of the conversion unit, and the output terminal is connected to the control terminal of the twenty-sixth switch M26; the first reference terminal of the fourth inverter A4 serves as the first reference terminal of the conversion unit, and the second reference terminal of the fourth inverter A4 serves as the second reference terminal of the conversion unit.

[0034] The control terminal of the 25th switch M25 is connected to the third voltage V3, and its current input terminal is connected to the current output terminal of the 27th switch M27; the current input terminal of the 26th switch M26 is connected to the current output terminal of the 28th switch M28; the current output terminals of the 25th switch M25 and the 26th switch M26 are both grounded.

[0035] The control terminal of the 27th switch M27 is connected to the control terminal of the 28th switch M28, and both are connected to the second external signal voltage VA.

[0036] In one possible implementation, the switching unit further includes a 29th switch M29, a 30th switch M30, a 31st switch M31, a 32nd switch M32, and an 8th resistor R8;

[0037] The current input terminal of the thirty-first switch M31, the current input terminal of the thirty-second switch M32, and the first terminal of the eighth resistor R8 are all connected to the internal signal voltage VS2, and the second terminal of the eighth resistor R8 is connected to the control terminal of the thirty-second switch M32.

[0038] The current output terminal of the thirty-first switch M31 is connected to the control terminal of the twenty-seventh switch M27 through the twenty-ninth switch M29. The current output terminal of the thirty-first switch M31 is also connected to the current input terminal of the twenty-seventh switch M27. The control terminal of the thirty-first switch M31 is connected to the control terminal of the twenty-ninth switch M29, and together they are connected to the current output terminal of the thirty-second switch M32.

[0039] The current output terminal of the thirty-second switch M32 is connected to the control terminal of the twenty-eighth switch M28 through the thirty-first switch M30. The current output terminal of the thirty-second switch M32 is also connected to the current input terminal of the twenty-eighth switch M28. The control terminal of the thirty-second switch M32 is connected to the control terminal of the thirty-first switch M30, and together they are connected to the current output terminal of the thirty-first switch M31.

[0040] In one possible implementation, the conversion unit further includes:

[0041] The fifth inverter A5 has its input terminal connected to the control terminal of the thirty-second switch M32, and its output terminal outputs the first voltage V1. The first reference terminal of the fifth inverter A5 serves as the third reference terminal of the conversion unit, and the second reference terminal of the fifth inverter A5 serves as the fourth reference terminal of the conversion unit.

[0042] In one possible implementation, the adjustment module includes a second comparison unit, an AND gate U1, a thirty-third switch M33, and a second voltage source;

[0043] The first terminal of the second comparison unit serves as the first reference terminal of the adjustment module, the second terminal of the second comparison unit serves as the second reference terminal of the adjustment module, and the output terminal of the second comparison unit is connected to the first input terminal of the AND gate U1; the second input terminal of the AND gate U1 is connected to the output terminal of the conversion unit to receive the first voltage V1 output by the conversion unit.

[0044] The first reference terminal of AND gate U1 and the current input terminal of the thirty-third switch M33 are both connected to the internal signal voltage VS2. The second reference terminal of AND gate U1 is connected to the second external signal voltage VA. The current output terminal of the thirty-third switch M33 is connected to the second external signal voltage VA through the second voltage source. The control terminal of the thirty-third switch M33 is connected to the output terminal of AND gate U1.

[0045] In one possible implementation, the circuit structure of the second comparison unit is the same as that of the first comparison unit.

[0046] According to the present invention, by setting up a signal processing module, an adjustment module, and a control module, when a power circuit malfunctions, the control module can output a control voltage to shut down the power circuit based on the first external signal voltage VS1, while simultaneously pulling down the internal signal voltage VS2. When the circuit recovers from the fault state to the normal state, the control module outputs a corresponding control voltage based on the internal signal voltage VS2, which is still at a low voltage level, and the first external signal voltage VS1, so that the power circuit can smoothly resume operation. This avoids transient overshoots in current or voltage at the output terminal of the power circuit due to excessively high internal signal voltage, thereby improving the stability of the circuit recovery process and the overall operational reliability of the system.

[0047] Furthermore, the first comparison unit uses the power supply voltage as the reference voltage, eliminating the need for an additional power input, simplifying the module structure, and reducing the overall circuit size. Simultaneously, its critical point voltage is temperature-independent, avoiding the impact of temperature drift on the comparison results, significantly improving the stability and accuracy of the voltage comparison process, and providing a reliable foundation for subsequent signal modulation.

[0048] Furthermore, when the circuit is in a fault state, the regulating module uses the current source BB and the 24th switch M24 to pull the external signal voltage VS2 down to the voltage VV1 of the first voltage source. When the circuit returns to normal, the internal signal voltage VS2 gradually increases from the voltage VV1, effectively preventing transient overshoots in voltage or current at the output terminal, thereby improving the safety and stability of the circuit during state switching.

[0049] Furthermore, by dynamically controlling the internal signal voltage VS2 through the adjustment module, the internal signal voltage VS2 is pulled down to a lower voltage level close to the second external signal voltage VA under circuit fault conditions. At the same time, during the response time when the circuit recovers from the fault to the normal state, the adjustment module continuously regulates the voltage difference between the internal signal voltage VS2 and the second external signal voltage VA, keeping it stably within the range of the voltage difference between VV2 and the preset voltage value. This avoids the internal signal voltage VS2 rising too quickly and causing transient overshoot of current or voltage, significantly improving the overshoot suppression capability and output stability of the circuit during state switching, and enhancing the safety and reliability of the overall circuit.

[0050] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below. Attached Figure Description

[0051] Figure 1 A schematic diagram of a protection circuit for suppressing transient overshoot according to an embodiment of the present invention is shown;

[0052] Figure 2 A schematic diagram of a protection circuit for suppressing transient overshoot according to another embodiment of the present invention is shown;

[0053] Figure 3 A protection circuit topology for suppressing transient overshoot is shown according to an embodiment of the present invention;

[0054] Figure 4 A schematic diagram of a protection circuit for suppressing transient overshoot according to another embodiment of the present invention is shown;

[0055] Figure 5 A circuit topology diagram of a conversion unit according to an embodiment of the present invention is shown;

[0056] Figure 6 A protection circuit topology for suppressing transient overshoot according to another embodiment of the present invention is shown. Detailed Implementation

[0057] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, it should be noted that, for ease of description, only the parts relevant to this application are shown in the accompanying drawings, not the entire structure. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this application.

[0058] The terms “comprising” and “having”, and any variations thereof, used in this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus.

[0059] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0060] Figure 1 A schematic diagram of a protection circuit for suppressing transient overshoot according to an embodiment of the present invention is shown. This protection circuit for suppressing transient overshoot is used to protect power circuits, such as… Figure 1 As shown, the protection circuit for suppressing transient overshoot includes a signal processing module 100, an adjustment module 200, and a control module 300 connected in sequence. The input terminal of the signal processing module 100 and the first input terminal of the control module 300 are both connected to a first external signal voltage VS1. The first reference terminal of the adjustment module 200 and the second input terminal of the control module 300 are both connected to an internal signal voltage VS2. The first reference terminal of the signal processing module 100 is connected to the chip input voltage VIN, the second reference terminal of the signal processing module 100 is grounded, and its output terminal is connected to the input terminal of the adjustment module 200. The signal processing module 100 is configured to output a first voltage V1 to the adjustment module 200 based on the first external signal voltage VS1 when a power circuit fault occurs, thereby reducing the internal signal voltage VS2. The output terminal of the control module 300 is connected to the power circuit and is used to output a control voltage to shut down the power circuit when the first external signal voltage VS1 is higher than a threshold voltage. The control module 300 is also configured to output a corresponding control voltage to the power circuit based on the first external signal voltage VS1 and the internal signal voltage VS2 when the power circuit returns to normal, so as to reduce the transient overshoot during the process of the power circuit recovering from the fault state to the normal state.

[0061] In this embodiment, the first external signal voltage VS1 is generated by the power circuit, the internal signal voltage VS2 is generated by the internal circuit of the chip, and the internal signal voltage VS2 has a charging circuit to charge it.

[0062] According to an embodiment of the present invention, by configuring a signal processing module 100, an adjustment module 200, and a control module 300, when a power circuit malfunctions, the control module can output a control voltage to shut down the power circuit based on a first external signal voltage VS1, while simultaneously pulling down the internal signal voltage VS2. When the circuit recovers from the fault state to the normal state, the control module 300 outputs a corresponding control voltage based on the internal signal voltage VS2, which is still at a low voltage level, and the first external signal voltage VS1, so that the power circuit can smoothly resume operation. This avoids transient overshoots in current or voltage at the output terminal of the power circuit due to excessively high internal signal voltage, thereby improving the stability of the circuit recovery process and the overall operational reliability of the system.

[0063] To further illustrate the specific structure and implementation of the protection circuit for suppressing transient overshoot, the present invention will be described in detail below with reference to specific embodiments.

[0064] Example 1:

[0065] Figure 2 A schematic diagram of a protection circuit for suppressing transient overshoot according to another embodiment of the present invention is shown. Figure 2 As shown, the signal processing module 100 includes a sampling unit 110, a first comparison unit 120, and a conversion unit 130. The input terminal of the sampling unit 110 serves as the input terminal of the signal processing module 100, its first reference terminal serves as the first reference terminal, and its second reference terminal serves as the second reference terminal. The first terminal of the first comparison unit 120 is connected to the sampling unit 110 to receive the second voltage V2 output by the sampling unit 110, and its second terminal is grounded. The input terminal of the conversion unit 130 is connected to the first comparison unit 120 to receive the third voltage V3 output by the first comparison unit 120, and its output terminal serves as the output terminal of the signal processing module 100. The first reference terminal of the conversion unit 130 is connected to the sampling unit 110 to receive the second voltage V2, its second reference terminal is grounded, and its third reference terminal is connected to the internal signal voltage VS2. The second reference terminal of the adjustment module 200 is grounded.

[0066] In this embodiment, the working principle of the protection circuit for suppressing transient overshoot is as follows: When the circuit is in a normal state, the first external signal voltage VS1 is lower than the threshold voltage, while the internal signal voltage VS2 remains at the voltage level of the normal working state. When the circuit malfunctions and enters a fault state, the first external signal voltage VS1 rises and exceeds the threshold voltage. At this time, the signal voltage VS1 is input to the control module 300, and the control module 300 outputs a control voltage VC to turn off the power circuit, thereby realizing the protection function. At the same time, the first external signal voltage VS1 is also processed by the sampling unit 110, the first comparison unit 120, and the conversion unit 130, and the first voltage V1 is output to the adjustment module 200, causing the internal signal voltage VS2 to be pulled low. When the circuit recovers from the fault state to the normal state, the internal signal voltage VS2 gradually rises from a low level. At this time, the control module 300 outputs the corresponding control voltage VC according to the relatively low first external signal voltage VS1 and the internal signal voltage VS2 to control the power circuit to conduct smoothly, thereby avoiding transient overshoot of voltage or current at the output of the power circuit and improving the stability and operational reliability of the power circuit during the recovery process.

[0067] Figure 3 A protection circuit topology for suppressing transient overshoot according to an embodiment of the present invention is shown. Figure 3 As shown, in the sampling unit 110, the chip input voltage VIN is grounded sequentially through a first resistor R1 and a first switch M1. The chip input voltage VIN is also grounded sequentially through a second resistor R2 and a second switch M2. Furthermore, the chip input voltage VIN is grounded sequentially through a third switch M3 and a fourth switch M4. Finally, the chip input voltage VIN is grounded sequentially through a fifth switch M5 and a sixth switch M6. The control terminal of the first switch M1 serves as the input terminal of the sampling unit 110. The control terminal of the second switch M2 is connected to the current output terminal of the fifth switch M5. The control terminal of the third switch M3 is connected to the current input terminal of the second switch M2. The control terminal of the fourth switch M4 is connected to the current input terminal of the fourth switch M4. The control terminal of the fifth switch M5 is connected to the current input terminal of the first switch M1. The control terminal of the sixth switch M6 is connected to the control terminal of the fourth switch M4.

[0068] In sampling unit 110, the chip input voltage VIN is grounded sequentially through the seventh switch M7, the eighth switch M8, the ninth switch M9, and the tenth switch M10; it is also grounded sequentially through the eleventh switch M11 and the twelfth switch M12; and further grounded sequentially through the third resistor R3 and the thirteenth switch M13. The control terminal of the seventh switch M7 is connected to the control terminal of the eleventh switch M11; the control terminal of the eighth switch M8 is connected to its current output terminal; the control terminal of the ninth switch M9 is connected to the current output terminal of the fifth switch M5; the control terminal of the tenth switch M10 is connected to the control terminal of the twelfth switch M12; the control terminal of the eleventh switch M11 is connected to its current output terminal; the control terminal of the twelfth switch M12 is connected to the control terminal of the thirteenth switch M13; and the control terminal of the thirteenth switch M13 is connected to its current input terminal. The voltage at the current output terminal of the seventh switch M7 is the second voltage V2.

[0069] Among them, the first resistor R1 and the second resistor R2 have the same resistance value, and the fourth switch M4 and the sixth switch M6 form a 1:1 current mirror structure.

[0070] In this embodiment, the working principle of the sampling unit 110 is as follows: After the circuit is powered on, the control terminal of the first switch transistor M1 is connected to the first external signal voltage VS1, the first switch transistor M1 is turned on, pulling down the voltage of the control terminal of the fifth switch transistor M5, causing the fifth switch transistor M5 to turn on, thereby pulling up the voltage of the control terminal of the second switch transistor M2, causing the second switch transistor M2 to turn on, then pulling down the voltage of the control terminal of the third switch transistor M3, causing the third switch transistor M3 to turn on, further pulling up the voltage of the control terminals of the fourth switch transistor M4 and the sixth switch transistor M6, causing the fourth switch transistor M4 and the sixth switch transistor M6 to turn on. At this time, since the resistance values ​​of the first resistor R1 and the second resistor R2 are equal, the voltage difference across the first resistor R1 and the second resistor R2 is proportional to the current flowing through the resistor. Simultaneously, according to... Figure 3As shown in the circuit structure, the current flowing through the first resistor R1 and the second resistor R2 is directly proportional to the control terminal voltages of the first switch M1 and the second switch M2, respectively. Therefore, when the control terminal voltage of the first switch M1 is large, i.e., when the first external signal voltage VS1 is large, the voltage difference across the first resistor R1 is greater than the voltage difference across the second resistor R2. Consequently, the current flowing through the fifth switch M5 is greater than the current flowing through the third switch M3. Furthermore, since the fourth switch M4 and the sixth switch M6 form a 1:1 current mirror structure, the current flowing through the fifth switch M5 is greater than the current flowing through the sixth switch M6, thus raising the control terminal voltage of the second switch M2. When the control terminal voltage of the first switch M1 is low, i.e., the first external signal voltage VS1 is low, the voltage difference across the first resistor R1 is less than the voltage difference across the second resistor R2. Therefore, the current flowing through the fifth switch M5 is less than the current flowing through the third switch M3, meaning the current flowing through the fifth switch M5 is less than the current flowing through the sixth switch M6, thus pulling down the control terminal voltage of the second switch M2. Finally, when the circuit reaches steady state, the control terminal voltages of both the first switch M1 and the second switch M2 are equal to the first external signal voltage VS1.

[0071] Simultaneously, after the circuit is powered on, the control terminal voltages of the tenth switch M10, the twelfth switch M12, and the thirteenth switch M13 are all pulled high by the third resistor R3, turning on the tenth switch M10, the twelfth switch M12, and the thirteenth switch M13. After the twelfth switch M12 turns on, it pulls down the control terminal voltages of the seventh switch M7 and the eleventh switch M11, turning on the seventh switch M7 and the eleventh switch M11. After the seventh switch M7 turns on, it pulls up the current input terminal voltage of the eighth switch M8, turning on the eighth switch M8. At the same time, the current input terminal voltage of the ninth switch M9 is pulled up through the seventh switch M7 and the eighth switch M8, thus turning on the ninth switch M9. Therefore, at this time, the second voltage V2 = VS1 + VGS9 + VGS8, where the eighth switch M8 can be composed of m switches with the same parameters and the same connection method connected in series. Therefore, the second voltage V2 = VS1 + VGS9 + m × VGS8. Wherein, VGS8 is the gate-source voltage difference when the eighth switch M8 is turned on, and VGS9 is the gate-source voltage difference when the ninth switch M9 is turned on.

[0072] As can be seen from the above analysis, the second voltage V2 is proportional to the first external signal voltage VS1, and even when the first external signal voltage VS1 is 0, the second voltage V2 still has a certain value, thereby ensuring that the subsequent first comparison unit 120 and conversion unit 130 work normally.

[0073] refer to Figure 3In the first comparison unit 120, the second voltage V2 is grounded sequentially through the fourth resistor R4 and the fifth resistor R5. The second voltage V2 is also grounded sequentially through the sixth resistor R6, the first transistor Q1 and the fourteenth switch M14. The second voltage V2 is also grounded sequentially through the sixth resistor R6, the seventh resistor R7, the second transistor Q2 and the fifteenth switch M15. The second voltage V2 is also grounded sequentially through the sixteenth switch M16 and the seventeenth switch M17. The second voltage V2 is also grounded sequentially through the eighteenth switch M18 and the nineteenth switch M19. The bases of transistors Q1 and Q2 are both connected to node B between resistors R4 and R5. The control terminal of transistor M14 is connected to its current input terminal. The control terminal of transistor M19 is connected to its control terminal. The control terminal of transistor M15 is connected to its current input terminal. The control terminal of transistor M17 is connected to its control terminal. The control terminal of transistor M16 is connected to its current output terminal. The control terminal of transistor M18 is connected to its control terminal. The voltage at the current output terminal of transistor M18 is the third voltage V3.

[0074] The ratio of the number of first transistors Q1 to the number of second transistors Q2 is 1:N.

[0075] In this embodiment, the working principle of the first comparison unit 120 is as follows: when the second voltage V2 is input into the first comparison unit 120, current is generated in each branch of the first comparison unit 120. Specifically, the current flowing through the sixth resistor R6 is denoted as IR6, the current flowing through the first transistor Q1 is denoted as IQ1, and the current flowing through the branch formed by the second transistor Q2 and the seventh resistor R7 is denoted as IQ2. At this time, according to the circuit structure, it can be obtained that... , , and you can get Where VR6 represents the voltage difference across the sixth resistor R6, and VBE1 represents the voltage difference between the base and emitter of the first transistor Q1. Furthermore, the ratio of the number of first transistors Q1 to the number of second transistors Q2 is 1:N, thus we can obtain... Where VBE2 represents the voltage difference between the base and emitter of the second transistor Q2, and VR7 represents the voltage difference across the seventh resistor R7. Since the fourteenth and nineteenth switches M14 and M19 form a 1:1 current mirror structure, the fifteenth and seventeenth switches M17 form a 1:1 current mirror structure, and the sixteenth and eighteenth switches M16 and M18 form a 1:1 current mirror structure, the current flowing through the fourteenth and nineteenth switches M14 and M19 is equal to current IQ1, and the current flowing through the fifteenth, seventeenth, sixteenth, and eighteenth switches M18 is equal to current IQ2. Therefore, when current IQ1 is greater than current IQ2, the third voltage V3 is pulled low to ground GND; when current IQ1 is less than current IQ2, the third voltage V3 is pulled high to the second voltage V2. Therefore, when the third voltage V3 is at the critical point, the current IQ1 = the current IQ2 = IO. At this time... Thus we can obtain That is, when the third voltage V3 is at the critical point, Therefore, when the third voltage V3 is at the critical point, the corresponding voltage value of the second voltage V2 can be obtained. When the first external signal voltage VS1 is greater than the threshold voltage, the second voltage V2 is greater than the voltage value V20, the voltage difference across the fourth resistor R4 is relatively large, and the voltage difference between the base and emitter of the first transistor Q1 and the second transistor Q2 is relatively large. Therefore, the current IQ2 is less than the current IQ1, and the third voltage V3 is pulled low to the voltage GND. Conversely, when the first external signal voltage VS1 is less than the threshold voltage, the second voltage V2 is less than the voltage value V20, the voltage difference across the fourth resistor R4 is relatively small, and the voltage difference between the base and emitter of the first transistor Q1 and the second transistor Q2 is relatively small. Therefore, the current IQ2 is greater than the current IQ1, and the third voltage V3 is pulled high to the second voltage V2.

[0076] Therefore, by setting the resistance values ​​of the fourth resistor R4, the fifth resistor R5, the sixth resistor R6, and the seventh resistor R7, as well as the ratio N of the second transistor Q2 to the first transistor Q1, the voltage value V20 can be adjusted, thereby setting the threshold voltage of the first external signal voltage VS1. Furthermore, since VT is a positive temperature parameter and VBE1 is a negative temperature parameter, by properly configuring the sixth resistor R6 and the seventh resistor R7, the voltage value V20 is unaffected by temperature, thus ensuring that the threshold voltage of the first external signal voltage VS1 is unaffected by temperature.

[0077] As can be seen from the above analysis, the first comparison unit 120 does not require an additional power input; the comparison voltage is the power supply voltage, thereby reducing the size of the first comparison unit 120. At the same time, the voltage value V20 is not affected by temperature, thus improving the accuracy of the first comparison unit 120.

[0078] refer to Figure 3 The conversion unit 130 includes a first inverter A1, a twentieth switch M20, a twenty-first switch M21, a twenty-second switch M22, and a twenty-third switch M23. The input terminal of the first inverter A1 serves as the input terminal of the conversion unit 130, its first reference terminal serves as the first reference terminal, and its second reference terminal serves as the second reference terminal. The current input terminal of the twentieth switch M20 is connected to the internal signal voltage VS2, and its current output terminal is grounded through the twenty-first switch M21. The current input terminal of the 22nd switch M22 is connected to the current input terminal of the 20th switch M20, and the current output terminal is grounded through the 23rd switch M23. The control terminal of the 20th switch M20 is connected to the current output terminal of the 22nd switch M22, and the control terminal of the 22nd switch M22 is connected to the current output terminal of the 20th switch M20. The control terminal of the 21st switch M21 is connected to the input terminal of the first inverter A1, and the control terminal of the 23rd switch M23 is connected to the output terminal of the first inverter A1.

[0079] refer to Figure 3 The conversion unit 130 also includes a second inverter A2 and a third inverter A3. The input terminal of the second inverter A2 is connected to the current output terminal of the twenty-second switching transistor M22. The first reference terminal of the second inverter A2 serves as the third reference terminal of the conversion unit 130, and the second reference terminal of the second inverter A2 serves as the second reference terminal of the conversion unit 130. The input terminal of the third inverter A3 is connected to the output terminal of the second inverter A2. The output terminal of the third inverter A3 outputs a first voltage V1. The first reference terminal of the third inverter A3 is connected to the first reference terminal of the second inverter A2, and the second reference terminal of the third inverter A3 is connected to the second reference terminal of the second inverter A2.

[0080] In this embodiment, the working principle of the conversion unit 130 is as follows: When the third voltage V3 is pulled high to the second voltage V2, the twenty-first switch M21 is turned on and the twenty-third switch M23 is turned off. The control terminal voltage of the twenty-second switch M22 is pulled low through the twenty-first switch M21, so the twenty-second switch M22 is turned on, thereby pulling up the input terminal voltage of the second inverter A2. At this time, the first voltage V1 output by the third inverter A3 is equal to the internal signal voltage VS2. When the third voltage V3 is pulled low to the ground voltage GND, the twenty-first switch M21 is turned off and the twenty-third switch M23 is turned on. The control terminal voltage of the twentieth switch M20 is pulled low through the twenty-third switch M23, so the twentieth switch M20 is turned on, thereby pulling up the control terminal voltage of the twenty-second switch M22, causing the twenty-second switch M22 to turn off. At this time, the input voltage of the second inverter A2 is pulled low by the twenty-third switch M23, and finally the first voltage V1 output by the third inverter A3 is equal to the ground voltage GND.

[0081] refer to Figure 3 In the adjustment module 200, the internal signal voltage VS2 is grounded in sequence through the 24th switch M24, the current source BB and the first voltage source. The control terminal of the 24th switch M24 is connected to the output terminal of the third inverter A3.

[0082] In this embodiment, the working principle of the adjustment module 200 is as follows: As can be seen from the above analysis, when the circuit is in a normal state, the first external signal voltage VS1 is lower than the threshold voltage, the second voltage V2 is lower than the voltage value V20, the third voltage V3 is pulled up to the second voltage V2, and the first voltage V1 output by the third inverter A3 is equal to the internal signal voltage VS2. At this time, the twenty-fourth switch M24 is in the off state, the adjustment module 200 does not work, and does not interfere with the circuit.

[0083] When the circuit enters a fault state, the first external signal voltage VS1 is higher than the threshold voltage, the second voltage V2 is higher than the voltage value V20, and the third voltage V3 is pulled low to ground voltage GND. The first voltage V1 output by the third inverter A3 is equal to ground voltage GND. At this time, the twenty-fourth switch M24 is turned on, and the internal signal voltage VS2 is pulled low to the voltage VV1 of the first voltage source through the current source BB and the twenty-fourth switch M24. This voltage VV1 is the minimum operating voltage of the regulation module 200 and the conversion unit 130.

[0084] When the circuit recovers from the fault state to the normal state, the first external signal voltage VS1 drops back below the threshold voltage, the twenty-fourth switch M24 is turned off, and the internal signal voltage VS2 gradually increases from the relatively low voltage VV1, ensuring that there is no transient overshoot at the output of the power circuit, thus improving the stability and safety of the power circuit operation.

[0085] According to the above embodiment, when the circuit is in a fault state, the adjustment module 200 uses the current source BB and the 24th switch M24 to pull the external signal voltage VS2 down to the voltage VV1 of the first voltage source. When the circuit returns to normal, the internal signal voltage VS2 gradually increases from the voltage VV1, effectively preventing transient overshoots in voltage or current at the output terminal, thereby improving the safety and stability of the circuit during state switching.

[0086] However, in practical applications, after the circuit recovers from a fault state to a normal state, a certain response time is still required before the switch can restart and output a signal. During this response process, the internal signal voltage VS2 has already begun to rise, possibly reaching a level much higher than voltage VV1 before the circuit starts operating. This could still cause transient overshoot in the voltage or current at the power circuit output, weakening the overshoot suppression effect. To further improve the overshoot suppression capability and ensure output stability during the circuit recovery process, this application proposes the following based on the above: Figure 4 Another protection circuit shown is designed to suppress transient overshoot, achieving a more stable and reliable dynamic response.

[0087] Example 2:

[0088] Figure 4 A schematic diagram of a protection circuit for suppressing transient overshoot according to another embodiment of the present invention is shown. Figure 4 As shown, the conversion unit 130 also includes a fourth reference terminal, and the adjustment module 200 also includes a second reference terminal. Both the fourth reference terminal of the conversion unit 130 and the second reference terminal of the adjustment module 200 are connected to a second external signal voltage VA. The second external signal voltage VA is positively correlated with the output current or output voltage of the power circuit. That is, after the circuit starts working, the larger the internal signal voltage VS2, the larger the output current or output voltage of the power circuit, and thus the larger the second external signal voltage VA. The adjustment module 200 is configured to adjust the internal signal voltage VS2 during the process of the power circuit returning from a fault state to a normal state, so that a preset voltage difference is maintained between the internal signal voltage VS2 and the second external signal voltage VA.

[0089] In this embodiment, the working principle of the protection circuit for suppressing transient overshoot is as follows: When the circuit is in a normal state, the first external signal voltage VS1 is lower than the threshold voltage, and the internal signal voltage VS2 is maintained at the voltage level required for normal operation. When the circuit enters a fault state, that is, when the first external signal voltage VS1 exceeds the threshold voltage, the first external signal voltage VS1 is input to the control module 300, and the protection circuit outputs a control voltage VC to shut down the power circuit to achieve the protection function. At this time, since the power circuit is shut down, the second external signal voltage VA drops rapidly to a lower value. Simultaneously, after the first external signal voltage VS1 is processed by the sampling module, the first comparison unit 120, and the conversion unit 130, a first voltage V1 is output. This first voltage V1 is input to the adjustment module 200, causing the adjustment module 200 to pull the internal signal voltage VS2 down to a lower level close to the second external signal voltage VA. Subsequently, when the circuit recovers from the fault state to the normal state, the adjustment module 200 controls the internal signal voltage VS2 and the second external signal voltage VA to always maintain a fixed voltage difference. During the response time after the circuit returns to normal from a fault state, no current or voltage is generated at the power circuit output terminal because the switching action has not yet started. At this time, the second external signal voltage VA remains at a low level, thus ensuring that the internal signal voltage VS2 will not rise abnormally during the initial response time of circuit recovery. After the response time ends and the circuit restarts, the control module 300 outputs the corresponding control voltage VC based on the low levels of the first external signal voltage VS1 and the internal signal voltage VS2, effectively controlling the power circuit and further enhancing the ability to suppress transient overshoot.

[0090] The protection circuit for suppressing transient overshoot in this second embodiment has the same circuit structure and working principle as the sampling unit 110 and the first comparison unit 120 in the first embodiment, and will not be described again here. The main difference between this second embodiment and the first embodiment lies in the different circuit structure and working principle of the conversion unit 130 and the adjustment module 200, which will be described in detail below with reference to the specific circuit.

[0091] Figure 5 A circuit topology diagram of a conversion unit 130 according to an embodiment of the present invention is shown. Figure 5As shown, the conversion unit 130 includes a 25th switch M25, a 26th switch M26, a 27th switch M27, a 28th switch M28, and a fourth inverter A4. The input terminal of the fourth inverter A4 serves as the input terminal of the conversion unit 130, and its output terminal is connected to the control terminal of the 26th switch M26. The first reference terminal of the fourth inverter A4 serves as the first reference terminal of the conversion unit 130, and its second reference terminal serves as the second reference terminal of the conversion unit 130. The control terminal of the 25th switch M25 is connected to a third voltage V3, and its current input terminal is connected to the current output terminal of the 27th switch M27. The current input terminal of the 26th switch M26 is connected to the current output terminal of the 28th switch M28. Both the current output terminals of the 25th and 26th switches are grounded. The control terminals of the 27th and 28th switches M28 are connected and both are connected to a second external signal voltage VA.

[0092] refer to Figure 5 The conversion unit 130 also includes a 29th switch M29, a 30th switch M30, a 31st switch M31, a 32nd switch M32, and an 8th resistor R8. The current input terminals of the 31st switch M31 and the 32nd switch M32, and the first terminal of the 8th resistor R8 are all connected to the internal signal voltage VS2. The second terminal of the 8th resistor R8 is connected to the control terminal of the 32nd switch M32. The current output terminal of the 31st switch M31 is connected to the control terminal of the 27th switch M27 through the 29th switch M29. The current output terminal of the 31st switch M31 is also connected to the current input terminal of the 27th switch M27. The control terminal of the 31st switch M31 is connected to the control terminal of the 29th switch M29, and both are connected to the current output terminal of the 32nd switch M32. The current output terminal of the 32nd switch M32 is connected to the control terminal of the 28th switch M28 through the 30th switch M30. The current output terminal of the 32nd switch M32 is also connected to the current input terminal of the 28th switch M28. The control terminal of the 32nd switch M32 is connected to the control terminal of the 30th switch M30, and together they are connected to the current output terminal of the 31st switch M31.

[0093] refer to Figure 5 The conversion unit 130 also includes a fifth inverter A5. The input terminal of the fifth inverter A5 is connected to the control terminal of the thirty-second switching transistor M32, and the output terminal outputs a first voltage V1. The first reference terminal of the fifth inverter A5 serves as the third reference terminal of the conversion unit 130, and is connected to the internal signal voltage VS2. The second reference terminal of the fifth inverter A5 serves as the fourth reference terminal of the conversion unit 130, and is connected to the second external signal voltage VA.

[0094] In this embodiment, the working principle of the conversion unit 130 is as follows: When the internal signal voltage VS2, the second external signal voltage VA, the second voltage V2, and the ground voltage GND are connected to the conversion unit 130, the control terminal voltage of the thirtieth switch M30 is pulled high through the eighth resistor R8, while its current output terminal voltage is the relatively low second external signal voltage VA. Therefore, the thirtieth switch M30 is turned on, which in turn pulls down the control terminal voltage of the thirty-first switch M31, making the thirty-first switch M31 turn on, and further ensuring that the control terminal voltage of the thirtieth switch M30 is pulled high. At the same time, since the voltages of the control terminal and current input terminal of the twenty-eighth switch M28 are both the second external signal voltage VA, the twenty-eighth switch M28 remains off. At this time, the current input terminal voltage of the twenty-seventh switch M27 is pulled high to the internal signal voltage VS2, while the control terminal voltage of the twenty-seventh switch M27 is the lower second external signal voltage VA. Therefore, the twenty-seventh switch M27 is turned on.

[0095] When the circuit is initially powered on and in normal operation, the first external signal voltage VS1 is lower than the threshold voltage. Therefore, the third voltage V3 output by the first comparator unit 120 is pulled high to the second voltage V2. At this time, the twenty-sixth switch M26 is off, and the twenty-fifth switch M25 is on. Current flows sequentially through the thirty-first switch M31, the twenty-seventh switch M27, and the twenty-fifth switch M25 to form a loop, clamping the control terminal voltage of the thirtieth switch M30 at VA+VGS27, where VGS27 is the gate-source voltage difference after the current flows through the twenty-seventh switch M27. At this time, the control terminal voltage of the thirtieth switch M30 is pulled low, turning off the thirtieth switch M30, turning on the thirty-second switch M32, and the control terminal voltage of the twenty-ninth switch M29 is pulled high, turning on the twenty-ninth switch M29, turning off the thirty-first switch M31, further ensuring that the control terminal voltage of the thirtieth switch M30 remains at a low level. At this time, the input voltage of the fifth inverter A5 is low, and the first voltage V1 output by the fifth inverter A5 is equal to the internal signal voltage VS2. That is, when the power circuit is in normal state, the conversion unit 130 outputs the internal signal voltage VS2.

[0096] When the circuit enters a fault state, the first external signal voltage VS1 is higher than the threshold voltage, so the third voltage V3 is pulled low to ground voltage GND, the 26th switch M26 turns on, and the 25th switch M25 turns off. At the same time, because the power circuit is in a normal state, the current input voltage of the 28th switch M28 has been pulled high to the internal signal voltage VS2, while the control terminal voltage of the 28th switch M28 is still the relatively low second external signal voltage VA. Therefore, the 28th switch M28 turns on, and the current flows sequentially through the 32nd switch M32, the 28th switch M28, and the 26th switch M26 to form a loop. At this time, the control terminal voltage of the 31st switch M31 is clamped to VA+VGS28, where VGS28 is the gate-source voltage difference after the current flows through the 28th switch M28. At this point, the control terminal voltage of the 31st switch M31 is pulled low, causing it to conduct, while the 29th switch M29 is turned off. The control terminal voltage of the 30th switch M30 is pulled high, turning it on, while the 32nd switch M32 is turned off, further ensuring that the control terminal voltage of the 31st switch M31 is pulled low. At this time, the input voltage of the fifth inverter A5 is high, and the first voltage V1 output by the fifth inverter A5 is equal to the second external signal voltage VA. That is, when the circuit is in a fault state, the conversion unit 130 outputs the second external signal voltage VA. Subsequently, after the circuit recovers from the fault state to the normal state, the conversion unit 130 re-outputs the internal signal voltage VS2.

[0097] Figure 6 A protection circuit topology for suppressing transient overshoot according to another embodiment of the present invention is shown. Figure 6 As shown, the adjustment module 200 includes a second comparison unit 210, an AND gate U1, a thirty-third switch M33, and a second voltage source. The first terminal of the second comparison unit 210 serves as the first reference terminal of the adjustment module 200, and the second terminal serves as the second reference terminal. The output terminal of the second comparison unit 210 is connected to the first input terminal of the AND gate U1 to output a fourth voltage V4 to the AND gate U1. The second input terminal of the AND gate U1 is connected to the output terminal of the conversion unit 130 to receive the first voltage V1 output by the conversion unit 130. The first reference terminal of the AND gate U1 and the current input terminal of the thirty-third switch M33 are both connected to the internal signal voltage VS2. The second reference terminal of the AND gate U1 is connected to the second external signal voltage VA. The current output terminal of the thirty-third switch M33 is connected to the second external signal voltage VA through the second voltage source. The control terminal of the thirty-third switch M33 is connected to the output terminal of the AND gate U1.

[0098] The circuit structure of the second comparison unit 210 is the same as that of the first comparison unit 120. The only difference is that the power supply voltage and input voltage of the first comparison unit 120 are both the first voltage V1 and the ground voltage GND, while the power supply voltage and input voltage of the second comparison unit 210 are both the internal signal voltage VS2 and the second external signal voltage VA. Therefore, the working principle of the second comparison unit 210 is basically the same as that of the first comparison unit 120, and will not be described in detail here.

[0099] Based on the working logic of the first comparison unit 120, the working principle of the second comparison unit 210 is as follows: when the difference between the internal signal voltage VS2 and the second external signal voltage VA is greater than a preset voltage difference, the fourth voltage V4 output by the second comparison unit 210 is equal to the second external signal voltage VA. When the difference between the internal signal voltage VS2 and the second external signal voltage VA is less than a preset voltage difference, the fourth voltage V4 output by the second comparison unit 210 is equal to the internal signal voltage VS2.

[0100] In this embodiment, the working principle of the adjustment module 200 is as follows: As analyzed in Embodiment 1 above, when the power circuit is in normal operation, the first external signal voltage VS1 is lower than the threshold voltage, the second voltage V2 is less than the voltage value V20, and the third voltage V3 is pulled up to the second voltage V2. The first voltage V1 output by the conversion unit 130 is equal to the internal signal voltage VS2. Simultaneously, when the circuit is in normal operation, both the internal signal voltage VS2 and the second external signal voltage VA are the voltages under normal operating conditions. The difference between the internal signal voltage VS2 and the second external signal voltage VA is less than the preset voltage difference. Therefore, the fourth voltage V4 output by the second comparison unit 210 is equal to the internal signal voltage VS2. Thus, at this time, both voltage signals input to the AND gate U1 (the third voltage V3 and the fourth voltage V4) are the internal signal voltage VS2, and the output voltage VD of the AND gate U1 is equal to the internal signal voltage VS2. At this time, the thirty-third switch M33 is in the off state, the adjustment module 200 does not work, and will not interfere with the circuit, thereby ensuring the normal operation of the system.

[0101] When the circuit is in a fault state, the first external signal voltage VS1 is higher than the threshold voltage, the second voltage V2 is greater than the voltage value V20, and the third voltage V3 is pulled down to ground voltage GND. The first voltage V1 output by the conversion unit 130 is equal to the second external signal voltage VA. Therefore, at this time, the output voltage VD of the AND gate U1 is equal to the second external signal voltage VA. At the same time, since the power circuit is turned off in the fault state, the second external signal voltage VA drops rapidly to a lower value, while the internal signal voltage VS2 is still maintained at the voltage level during normal operation. Therefore, the internal signal voltage VS2 is much greater than the second external signal voltage VA, forming a large voltage difference between the two. At this time, the thirty-third switch M33 is turned on, and the internal signal voltage VS2 is pulled down to a lower value close to the second external signal voltage VA, VA+VV2, through the thirty-third switch M33. Here, the voltage VV2 of the second voltage source is the minimum operating voltage difference between the regulation module 200 and the conversion unit 130 provided by the second voltage source, ensuring that the regulation module 200 and the conversion unit 130 can still maintain basic operation, thereby achieving effective suppression of transient overshoot.

[0102] When the circuit returns to normal operation from a fault state, the first external signal voltage VS1 drops below the threshold voltage. The first voltage V1 output by the conversion unit 130 is equal to the internal signal voltage VS2, which is a relatively low voltage VA+VV2. During the response time after the circuit returns to normal operation from a fault state, since the switches in the circuit have not yet been turned on, no current or voltage is generated at the power circuit output, and the second external signal voltage VA remains at a low value. During this period, the internal signal voltage VS2 begins to rise slowly from VA+VV2. When the voltage difference between the internal signal voltage VS2 and the second external signal voltage VA exceeds the preset voltage difference value, the fourth voltage V4 output by the second comparison unit 210 is the second external signal voltage VA, causing the thirty-third switch M33 to conduct. The internal signal voltage VS2 is pulled down by the thirty-third switch M33 to a lower value close to the second external signal voltage VA+VV2. Therefore, during the response time, the regulating module 200 controls the voltage difference between the internal signal voltage VS2 and the second external signal voltage VA to remain between voltage VV2 and the preset voltage difference, thereby effectively preventing the internal signal voltage VS2 from abnormally increasing during the response period. When the response time ends and the power circuit resumes operation, the control module 300 outputs a corresponding control voltage VC based on the relatively low first external signal voltage VS1 and internal signal voltage VS2 to control the power circuit. Both the internal signal voltage VS2 and the second external signal voltage VA begin to increase until they reach their normal operating values.

[0103] When the circuit returns to normal, the first external signal voltage VS1 is lower than the threshold voltage. The first voltage V1 output by the conversion unit 130 is equal to the internal signal voltage VS2. At the same time, when the circuit is in normal condition, the difference between the internal signal voltage VS2 and the second external signal voltage VA is less than the preset voltage difference. The fourth voltage V4 output by the second comparison unit 210 is the internal signal voltage VS2. Therefore, at this time, both inputs of AND gate U1 are the internal signal voltage VS2, and the output voltage VD of AND gate U1 is the internal signal voltage VS2. The thirty-third switch M33 remains off, and the adjustment module 200 is in the off state, which does not affect the normal operation of the circuit.

[0104] As can be seen from the above analysis, during the response time when the circuit recovers from the fault state to the normal state, the adjustment module 200 always controls the voltage difference between the internal signal voltage VS2 and the second external signal voltage VA to be maintained between the voltage VV2 and the preset voltage difference value, thereby avoiding the abnormal rise of the internal signal voltage VS2 during this stage, ensuring that there will be no transient overshoot at the circuit output, and improving the suppression effect and overall stability of the protection circuit during the state switching process.

[0105] According to the above embodiment, by dynamically controlling the internal signal voltage VS2 through the adjustment module 200, the internal signal voltage VS2 is pulled down to a lower voltage level close to the second external signal voltage VA under circuit fault conditions. At the same time, during the response time when the circuit recovers from the fault to the normal state, the adjustment module 200 continuously regulates the voltage difference between the internal signal voltage VS2 and the second external signal voltage VA, keeping it stably within the range of the voltage VV2 and the preset voltage difference value. This avoids the internal signal voltage VS2 rising too quickly and causing transient overshoot of current or voltage, significantly improving the overshoot suppression capability and output stability of the circuit during state switching, and enhancing the safety and reliability of the overall circuit.

[0106] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0107] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A protection circuit for suppressing a transient overshoot, characterized by comprising: The protection circuit is integrated in a semiconductor integrated circuit chip and used for protecting a power circuit, and comprises a signal processing module, an adjusting module and a control module connected in sequence; The input end of the signal processing module and the first input end of the control module are connected to a first external signal voltage VS1; the first reference end of the adjusting module and the second input end of the control module are connected to an internal signal voltage VS2, the first external signal voltage VS1 is generated by the power circuit, and the internal signal voltage VS2 is generated by an internal circuit of the semiconductor integrated circuit chip; The first reference end of the signal processing module is connected to a chip input voltage VIN, the second reference end of the signal processing module is grounded, the output end of the signal processing module is connected to the input end of the adjusting module, and the signal processing module is configured to output a first voltage V1 to the adjusting module according to the first external signal voltage VS1 when the power circuit fails, so that the internal signal voltage VS2 is reduced; The output end of the control module is connected to the power circuit, and the control module is configured to output a control voltage to turn off the power circuit when the first external signal voltage VS1 is higher than a threshold voltage; and the control module is further configured to output a corresponding control voltage to the power circuit according to the first external signal voltage VS1 and the internal signal voltage VS2 when the power circuit returns to normal, so as to reduce a transient overshoot in the process of returning the power circuit from a failure state to a normal state.

2. The protection circuit of claim 1, wherein, The signal processing module comprises: a sampling unit, an input end of the sampling unit serving as an input end of the signal processing module, a first reference end of the sampling unit serving as a first reference end of the signal processing module, and a second reference end of the sampling unit serving as a second reference end of the signal processing module; a first comparison unit, a first end of the first comparison unit being connected to the sampling unit to receive a second voltage V2 output by the sampling unit, and a second end of the first comparison unit being grounded; a conversion unit, an input end of the conversion unit being connected to the first comparison unit to receive a third voltage V3 output by the first comparison unit, and an output end of the conversion unit serving as an output end of the signal processing module; a first reference end of the conversion unit being connected to the sampling unit to receive the second voltage V2, a second reference end of the conversion unit being grounded, and a third reference end of the conversion unit being connected to the internal signal voltage VS2.

3. The protection circuit of claim 2, wherein, In the sampling unit, the chip input voltage VIN is grounded in sequence through a first resistor R1 and a first switch tube M1; the chip input voltage VIN is also grounded in sequence through a second resistor R2 and a second switch tube M2; the chip input voltage VIN is also grounded in sequence through a third switch tube M3 and a fourth switch tube M4; and the chip input voltage VIN is also grounded in sequence through a fifth switch tube M5 and a sixth switch tube M6. The control end of the first switch tube M1 is used as the input end of the sampling unit, the control end of the second switch tube M2 is connected to the current output end of the fifth switch tube M5, the control end of the third switch tube M3 is connected to the current input end of the second switch tube M2, the control end of the fourth switch tube M4 is connected to the current input end of the fourth switch tube M4, the control end of the fifth switch tube M5 is connected to the current input end of the first switch tube M1, and the control end of the sixth switch tube M6 is connected to the control end of the fourth switch tube M4.

4. The protection circuit of claim 3, wherein, In the sampling unit, the chip input voltage VIN is grounded through the seventh switch tube M7, the eighth switch tube M8, the ninth switch tube M9 and the tenth switch tube M10 in sequence; the chip input voltage VIN is grounded through the eleventh switch tube M11 and the twelfth switch tube M12 in sequence; the chip input voltage VIN is grounded through the third resistor R3 and the thirteenth switch tube M13 in sequence; The control end of the seventh switch tube M7 is connected to the control end of the eleventh switch tube M11, the control end of the eighth switch tube M8 is connected to the current output end of the eighth switch tube M8, the control end of the ninth switch tube M9 is connected to the current output end of the fifth switch tube M5, the control end of the tenth switch tube M10 is connected to the control end of the twelfth switch tube M12, the control end of the eleventh switch tube M11 is connected to the current output end of the eleventh switch tube M11, the control end of the twelfth switch tube M12 is connected to the control end of the thirteenth switch tube M13, and the control end of the thirteenth switch tube M13 is connected to the current input end of the thirteenth switch tube M13; The current output end voltage of the seventh switch tube M7 is the second voltage V2.

5. The protection circuit of claim 4, wherein, In the first comparison unit, the second voltage V2 is grounded through the fourth resistor R4 and the fifth resistor R5 in sequence; the second voltage V2 is grounded through the sixth resistor R6, the first triode Q1 and the fourteenth switch tube M14 in sequence; the second voltage V2 is grounded through the sixth resistor R6, the seventh resistor R7, the second triode Q2 and the fifteenth switch tube M15 in sequence; the second voltage V2 is grounded through the sixteenth switch tube M16 and the seventeenth switch tube M17 in sequence; and the second voltage V2 is grounded through the eighteenth switch tube M18 and the nineteenth switch tube M19 in sequence; The base of the first triode Q1 and the second triode Q2 is connected between the fourth resistor R4 and the fifth resistor R5; the control end of the fourteenth switch tube M14 is connected to the current input end of the fourteenth switch tube M14, and the control end of the nineteenth switch tube M19 is connected to the control end of the fourteenth switch tube M14; the control end of the fifteenth switch tube M15 is connected to the current input end of the fifteenth switch tube M15, and the control end of the seventeenth switch tube M17 is connected to the control end of the fifteenth switch tube M15; the control end of the sixteenth switch tube M16 is connected to the current output end of the sixteenth switch tube M16, and the control end of the eighteenth switch tube M18 is connected to the control end of the sixteenth switch tube M16. The current output end voltage of the eighteenth switch tube M18 is the third voltage V3.

6. The protection circuit of claim 5, wherein, The number ratio of the first triode Q1 and the second triode Q2 is 1:N.

7. The protection circuit of claim 6, wherein, The adjusting module further comprises a second reference end, and the second reference end of the adjusting module is grounded.

8. The protection circuit of claim 7, wherein, The conversion unit comprises a first inverter A1, a twentieth switch tube M20, a twenty-first switch tube M21, a twenty-second switch tube M22, a twenty-third switch tube M23; The input end of the first inverter A1 serves as the input end of the conversion unit, the first reference end of the first inverter A1 serves as the first reference end of the conversion unit, and the second reference end of the first inverter A1 serves as the second reference end of the conversion unit; The current input end of the twentieth switch tube M20 is connected to the internal signal voltage VS2, and the current output end is grounded through the twenty-first switch tube M21; the current input end of the twenty-second switch tube M22 is connected to the current input end of the twentieth switch tube M20, and the current output end is grounded through the twenty-third switch tube M23; the control end of the twentieth switch tube M20 is connected to the current output end of the twenty-second switch tube M22, and the control end of the twenty-second switch tube M22 is connected to the current output end of the twentieth switch tube M20; the control end of the twenty-first switch tube M21 is connected to the input end of the first inverter A1, and the control end of the twenty-third switch tube M23 is connected to the output end of the first inverter A1.

9. The protection circuit of claim 8, wherein, The conversion unit further comprises: a second inverter A2, the input end of which is connected to the current output end of the twenty-second switch tube M22, the first reference end of the second inverter A2 serving as the third reference end of the conversion unit, and the second reference end of the second inverter A2 serving as the second reference end of the conversion unit; a third inverter A3, the input end of which is connected to the output end of the second inverter A2, the output end of the third inverter A3 outputting the first voltage V1, the first reference end of the third inverter A3 being connected to the first reference end of the second inverter A2, and the second reference end of the third inverter A3 being connected to the second reference end of the second inverter A2.

10. The protection circuit of claim 9, wherein, In the adjusting module, the internal signal voltage VS2 is sequentially connected to the twenty-fourth switch tube M24, the current source BB and the first voltage source ground; the control end of the twenty-fourth switch tube M24 is connected to the output end of the third inverter A3.

11. The protection circuit of claim 6, wherein, The adjusting module further comprises a second reference end, and the conversion unit further comprises a fourth reference end, wherein the fourth reference end of the conversion unit and the second reference end of the adjusting module are connected to a second external signal voltage VA, and the second external signal voltage VA is positively correlated with the output current or the output voltage of the power circuit; The adjusting module is configured to adjust the internal signal voltage VS2 so that a preset voltage difference is maintained between the internal signal voltage VS2 and the second external signal voltage VA during the process that the power circuit returns to the normal state from the fault state.

12. The protection circuit of claim 11, wherein, The conversion unit comprises a twenty-fifth switch tube M25, a twenty-sixth switch tube M26, a twenty-seventh switch tube M27, a twenty-eighth switch tube M28 and a fourth inverter A4; The input end of the fourth inverter A4 serves as the input end of the conversion unit, and the output end is connected to the control end of the twenty-sixth switch tube M26; the first reference end of the fourth inverter A4 serves as the first reference end of the conversion unit, and the second reference end of the fourth inverter A4 serves as the second reference end of the conversion unit; The control end of the twenty-fifth switch tube M25 is connected to the third voltage V3, and the current input end is connected to the current output end of the twenty-seventh switch tube M27; the current input end of the twenty-sixth switch tube M26 is connected to the current output end of the twenty-eighth switch tube M28; and the current output end of the twenty-fifth switch tube M25 and the current output end of the twenty-sixth switch tube M26 are both grounded; The control end of the twenty-seventh switch tube M27 is connected to the control end of the twenty-eighth switch tube M28, and both are connected to the second external signal voltage VA.

13. The protection circuit of claim 12, wherein, The conversion unit further comprises a twenty-ninth switch tube M29, a thirtieth switch tube M30, a thirty-first switch tube M31, a thirty-second switch tube M32 and an eighth resistor R8; The current input end of the thirty-first switch tube M31, the current input end of the thirty-second switch tube M32 and the first end of the eighth resistor R8 are all connected to the internal signal voltage VS2, and the second end of the eighth resistor R8 is connected to the control end of the thirty-second switch tube M32; The current output end of the thirty-first switch tube M31 is connected to the control end of the twenty-seventh switch tube M27 through the twenty-ninth switch tube M29, and the current output end of the thirty-first switch tube M31 is also connected to the current input end of the twenty-seventh switch tube M27; the control end of the thirty-first switch tube M31 is connected to the control end of the twenty-ninth switch tube M29, and both are connected to the current output end of the thirty-second switch tube M32; The current output end of the thirty-second switch tube M32 is connected to the control end of the twenty-eighth switch tube M28 through the thirtieth switch tube M30, and the current output end of the thirty-second switch tube M32 is also connected to the current input end of the twenty-eighth switch tube M28; the control end of the thirty-second switch tube M32 is connected to the control end of the thirtieth switch tube M30, and is also connected to the current output end of the thirty-first switch tube M31.

14. The protection circuit of claim 13, wherein, The conversion unit further comprises: A fifth inverter A5, whose input end is connected to the control end of the thirty-second switch tube M32, and whose output end outputs the first voltage V1; the first reference end of the fifth inverter A5 is the third reference end of the conversion unit, and the second reference end of the fifth inverter A5 is the fourth reference end of the conversion unit.

15. The protection circuit of claim 14, wherein, The adjustment module comprises a second comparison unit, an AND gate U1, a thirty-third switch tube M33 and a second voltage source; The first end of the second comparison unit is the first reference end of the adjustment module, and the second end of the second comparison unit is the second reference end of the adjustment module; the output end of the second comparison unit is connected to the first input end of the AND gate U1; the second input end of the AND gate U1 is connected to the output end of the conversion unit to receive the first voltage V1 output by the conversion unit; The first reference end of the AND gate U1 and the current input end of the thirty-third switch tube M33 are connected to the internal signal voltage VS2, the second reference end of the AND gate U1 is connected to the second external signal voltage VA, and the current output end of the thirty-third switch tube M33 is connected to the second external signal voltage VA through the second voltage source; the control end of the thirty-third switch tube M33 is connected to the output end of the AND gate U1.

16. The protection circuit of claim 15, wherein, The circuit structure of the second comparison unit is the same as that of the first comparison unit.

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