High-precision surge protection circuit, power supply connecting line, equipment and system

Abstract

The utility model provides a high-precision surge protection circuit, a power supply connecting line, equipment and a system, a first end of the circuit is coupled to a path between a power supply input end and a power supply output end, a second end of the circuit is grounded, the circuit compares a path voltage with a trigger voltage through a surge detection module, and the voltage of the path voltage and the trigger voltage is detected. Only when the comparison result represents that the surge occurs on the access, the power supply module is controlled to supply power to the discharge control module, so that the reference voltage source unit outputs a reference voltage, the comparison unit performs first processing on the reference voltage and the voltage of the second end of the first resistor, and outputs a corresponding first voltage to the control end of the discharge switch; therefore, the conduction degree of the discharge switch is controlled, and the voltage of the output end of the power supply is accurately clamped to a set clamping voltage. And when the comparison result shows that no surge occurs on the path, the power supply module is controlled to stop supplying power to the discharge control module, so that the discharge control module stops working, and the loss generated by the circuit is reduced.

Description

[0001] Cross-references to related applications

[0002] This application is based on and claims priority to application number CN202410245652.5 filed on March 5, 2024, with the China Patent and Trademark Office, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] This invention relates to the field of power electronics technology, and in particular to a high-precision surge protection circuit, power connection line, electronic device, and charging system. Background Technology

[0004] Electronic devices often generate transient voltages when switching power, such as pulse voltages, electrostatic discharge, and surge voltages. Among these, surge voltages, due to their high energy and large overcurrent, are particularly harmful to circuits, easily causing damage. Furthermore, the cumulative effect of multiple small surges can degrade the performance of semiconductor devices. Therefore, to protect electronic devices from damage during surges, surge suppression circuits need to be added to the power input ports of the electronic devices.

[0005] Currently, surge suppression methods mainly include: inserting appropriate linear impedances into the circuit to suppress power-on surge current (e.g., Yao Likun, Yao Fei, Fu Zongbao, et al. Research on Design and Application of Surge Suppression Circuit for Spacesuits [J]. Computer Measurement & Control, 2021, 29(03):220-223.DOI:10.16526 / j.cnki.11-4762 / tp.2021.03.043.), connecting a specific surge suppression chip in series in the circuit (e.g., CN116054115B), and connecting TVS devices in parallel with the subsequent circuit (e.g., Dong Dawei, Li Jiangling. Research and Design of a Surge Protection Circuit [J]. Electronic Technology Application, 2020, 46(07):74-77.DOI:10.16157 / j.issn.0258-7998.200395.).

[0006] However, the existing practices described above have the following problems:

[0007] 1) For circuits that insert appropriate linear impedances to suppress start-up surge current, the resistance value can be affected by process and temperature, so they are only suitable for equipment with low requirements for ambient temperature.

[0008] 2) For a circuit with a specific surge suppression chip connected in series in the circuit, although the surge energy can be absorbed by driving the internal MOS transistor to work in the subthreshold region when a surge occurs, its on-resistance is relatively large when the circuit is working normally, which will generate unnecessary heat and thus affect the reliability of the device.

[0009] 3) For circuits that connect TVS devices in parallel with subsequent circuits, the cost is high, the junction capacitance of the circuit is large, the clamping (protection) voltage value cannot be designed arbitrarily, and the resulting leakage current is relatively large.

[0010] Therefore, how to clamp the output voltage of the control circuit to a set value in the event of a surge voltage, while ensuring that there is no impedance between the input and output terminals of the power supply line, has become a technical problem that the industry urgently needs to solve. Summary of the Invention

[0011] This invention provides a high-precision surge protection circuit, power connection line, electronic device, and charging system to solve the problem of how to clamp the output voltage of the control circuit to a set value in the event of a surge voltage, while also taking into account the lack of impedance between the input and output ends of the power line.

[0012] According to a first aspect of the present invention, a high-precision surge protection circuit is provided, wherein a first terminal is coupled to a power input terminal and a power output terminal respectively, and a second terminal is grounded; the high-precision surge protection circuit includes a surge detection module, a power module, a discharge control module and a discharge switch; the discharge control module includes a reference voltage source unit, a comparison unit, a first resistor and a second resistor;

[0013] The first terminal of the surge detection module, the first terminal of the first resistor, and the first terminal of the discharge switch are all coupled to the power input terminal and the power output terminal, respectively; the second terminal of the surge detection module is coupled to the input terminal of the power module, and its third terminal is grounded; the output terminal of the power module is coupled to the input terminal of the reference voltage source unit and the first terminal of the comparator unit; the output terminal of the reference voltage source unit is coupled to the first input terminal of the comparator unit, the second terminal of the first resistor is coupled to the second input terminal of the comparator unit and the first terminal of the second resistor, and the second terminal of the second resistor is grounded; the output terminal of the comparator unit is coupled to the control terminal of the discharge switch, and the second terminal of the discharge switch is grounded, wherein:

[0014] The surge detection module is used to compare the magnitudes of the path voltage and the trigger voltage, and only controls the power module to supply power to the discharge control module when the comparison result indicates that a surge has occurred in the path between the power input terminal and the power output terminal; otherwise, it controls the power module to stop supplying power to the discharge control module.

[0015] The reference voltage source unit is configured to output a reference voltage only when the power module supplies power to the discharge control module; otherwise, it outputs the power ground voltage.

[0016] The comparison unit is configured to:

[0017] When the power module supplies power to the discharge control module, the reference voltage and the voltage at the second end of the first resistor are processed first, and the corresponding first voltage is output to the control terminal of the discharge switch to control the conduction degree of the discharge switch and clamp the voltage at the power output terminal to the clamping voltage; the first processing includes at least subtraction amplification processing.

[0018] When the power module stops supplying power to the discharge control module, the power supply ground voltage is output to the control terminal of the discharge switch to control the discharge switch to turn off.

[0019] Optionally, the clamping voltage value is configured as follows:

[0020]

[0021] Among them, V CLAMP The clamping voltage value is V, where R1 is the resistance value of the first resistor, R2 is the resistance value of the second resistor, and V is the clamping voltage value. IN+ The reference voltage is the voltage value.

[0022] Optionally, the comparison unit includes an amplifier, a first PMOS transistor, a third resistor, and a first pull-down sub-unit;

[0023] The amplifier's power supply terminal is coupled to the output terminal of the power module, its non-inverting input terminal is coupled to the output terminal of the reference voltage source unit, its inverting input terminal is coupled to the second terminal of the first resistor, its output terminal is coupled to the control terminal of the first PMOS transistor, the source of the first PMOS transistor is coupled to the output terminal of the power module, and its drain is coupled to the first terminal of the first pull-down subunit and the first terminal of the third resistor, respectively. The second terminal of the first pull-down subunit is grounded; the second terminal of the third resistor is coupled to the control terminal of the bleeder switch to output the corresponding first voltage or the power supply ground voltage; wherein:

[0024] The amplifier is configured to:

[0025] When the power module supplies power to the discharge control module, it compares the voltage value received at its non-inverting input terminal with the voltage value received at its inverting input terminal. If the voltage value received at its non-inverting input terminal is greater than the voltage value received at its inverting input terminal, it outputs the power supply voltage of the power module.

[0026] If the voltage value received at its non-inverting input terminal is less than or equal to the voltage value received at its inverting input terminal, the reference voltage and the voltage at the second terminal of the first resistor are subtracted and amplified, and the corresponding second voltage value is output. The control terminal of the first PMOS transistor controls the conduction degree of the first PMOS transistor and clamps the voltage at the power output terminal to the clamping voltage.

[0027] Optionally, the discharge switch is an NMOS transistor.

[0028] Optionally, the first pull-down sub-unit includes a resistor.

[0029] Optionally, the power module includes a second PMOS transistor, a first capacitor, a fifth resistor, a third PMOS transistor, a first NMOS transistor, a second NMOS transistor, a fourth PMOS transistor, a sixth resistor, and a first diode;

[0030] The source and gate of the second PMOS transistor are both coupled to the second terminal of the surge detection module. The drain of the second PMOS transistor is coupled to the first terminal of the first capacitor, the first terminal of the fifth resistor, the gate of the third PMOS transistor, and the gate of the first NMOS transistor. The second terminal of the first capacitor and the second terminal of the fifth resistor are both grounded. The source of the third PMOS transistor is coupled to the gate of the second PMOS transistor. The drain of the third PMOS transistor is coupled to the drain of the first NMOS transistor and the gate of the fourth PMOS transistor. The source of the first NMOS transistor is grounded. The source of the fourth PMOS transistor is coupled to the source of the second NMOS transistor. The drain of the second NMOS transistor is coupled to the first terminal of the surge detection module, and its gate is coupled to the gate of the second PMOS transistor. The drain of the fourth PMOS transistor is coupled to the first terminal of the sixth resistor and the cathode of the first diode. The second terminal of the sixth resistor and the anode of the first diode are both grounded.

[0031] Optionally, the first pull-down sub-unit includes a pull-down current source.

[0032] Optionally, the comparison unit further includes a second pull-down subunit;

[0033] The first end of the second pull-down subunit is coupled to the second end of the third resistor, and the second end of the second pull-down subunit is grounded.

[0034] Optionally, the second pull-down submodule includes a seventh resistor, a third NMOS transistor, and a fourth NMOS transistor;

[0035] The first end of the seventh resistor is coupled to the positive terminal of the first diode, and its second end is coupled to the drain of the third NMOS transistor and the gate of the fourth NMOS transistor. The gate of the third NMOS transistor is coupled to the first end of the fifth resistor, and its source is grounded. The drain of the fourth NMOS transistor is coupled to the second end of the third resistor, and its source is grounded.

[0036] Optionally, the surge detection module includes a first Zener diode, a second Zener diode, a third Zener diode, a fourth resistor, and a fourth Zener diode connected in series.

[0037] The first end of the first Zener diode is coupled to the power input terminal, the fourth Zener diode is grounded, and the first and second ends of the fourth resistor are respectively coupled to the first and second input terminals of the power module to output the comparison result to the power module.

[0038] Optionally, the trigger voltage is the sum of the Zener voltage of the first Zener diode, the Zener voltage of the second Zener diode, and the Zener voltage of the third Zener diode.

[0039] Optionally, the surge detection module includes at least one Zener diode.

[0040] Optionally, the trigger voltage is greater than the clamping voltage.

[0041] Optionally, the trigger voltage is less than or equal to the clamping voltage.

[0042] Optionally, the power module includes a second capacitor; the second capacitor is connected in parallel with the fourth resistor.

[0043] According to a second aspect of the present invention, a power connection line is provided to provide a charging connection between a power supply device and an equipment, including a voltage bus and a high-precision surge protection circuit as described in any of the first aspects of the present invention connected in parallel on the voltage bus.

[0044] According to a third aspect of the present invention, an electronic device is provided, comprising the high-precision surge protection circuit provided in any of the first aspects of the present invention.

[0045] According to a fourth aspect of the present invention, a charging system is provided, including the high-precision surge protection circuit provided in the third aspect of the present invention.

[0046] The high-precision surge protection circuit, power connection line, electronic device, and charging system provided by this invention have a first terminal coupled to a power input terminal and a power output terminal, and a second terminal grounded. The circuit compares the path voltage and trigger voltage using a surge detection module. Only when the comparison result indicates a surge in the path between the power input terminal and the power output terminal, the circuit controls the power module to supply power to the discharge control module, causing the reference voltage source unit to output a reference voltage. The comparison unit performs a first processing on the reference voltage and the voltage at the second terminal of the first resistor, and outputs a corresponding first voltage to the control terminal of the discharge switch to control the conduction degree of the discharge switch, precisely clamping the voltage at the power output terminal to the set clamping voltage. When the comparison result indicates no surge in the path between the power input terminal and the power output terminal, the circuit controls the power module to stop supplying power to the discharge control module, causing the discharge control module to stop working and reducing circuit losses. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 This is a schematic diagram of the high-precision surge protection circuit in an embodiment of the present invention;

[0049] Figure 2 This is a schematic diagram of the high-precision surge protection circuit in the first embodiment of the present invention;

[0050] Figure 3 This is a schematic diagram of the construction of a high-precision surge protection circuit in the second embodiment of the present invention;

[0051] Figure 4 This is a schematic diagram of the construction of a high-precision surge protection circuit in the third embodiment of the present invention;

[0052] Figure 5 This is a schematic diagram of the construction of a high-precision surge protection circuit in the fourth embodiment of the present invention;

[0053] Figure 6 This is a schematic diagram of the construction of a high-precision surge protection circuit in the fifth embodiment of the present invention;

[0054] Figure 7 This is a schematic diagram of the construction of a high-precision surge protection circuit in the sixth embodiment of the present invention;

[0055] Figure 8This is a schematic diagram of the construction of a high-precision surge protection circuit in the seventh embodiment of the present invention;

[0056] Figure 9 This is a schematic diagram of the construction of a high-precision surge protection circuit in the eighth embodiment of the present invention;

[0057] Figure 10 This is a schematic diagram of the construction of a high-precision surge protection circuit in the ninth embodiment of the present invention;

[0058] Figure 11 This is a flowchart of the high-precision surge protection method in an embodiment of the present invention;

[0059] Figure 12 This is a schematic diagram of the power connection wire structure in an embodiment of the present invention.

[0060] Explanation of reference numerals in the attached figures:

[0061] 1-High-precision surge protection circuit;

[0062] Vin - Power input terminal;

[0063] Vout - Power output terminal;

[0064] 10-Surge detection module;

[0065] 20-Power supply module;

[0066] 30 - Discharge control module;

[0067] 301 - Reference Voltage Source Unit;

[0068] 302 - Comparison Unit;

[0069] 3021 - Amplifier;

[0070] 3022 - First drop-down sub-unit;

[0071] 3023 - Second drop-down sub-unit;

[0072] Q1 - First PMOS transistor;

[0073] Q2 - Discharge switch;

[0074] R1 - First resistor;

[0075] R2 - Second resistor;

[0076] R3 - Third resistor;

[0077] R4 - Fourth resistor;

[0078] Z1 - First Zener diode;

[0079] Z2 - Second Zener diode;

[0080] Z3 - Third Zener diode;

[0081] Z4 - Fourth Zener diode;

[0082] Z5 - Fifth Zener diode;

[0083] C1 - First capacitor. Detailed Implementation

[0084] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0085] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0086] The technical solution of the present invention will be described in detail below with reference to specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0087] Given that existing technologies often struggle to clamp the output voltage of a control circuit to a set value in the event of a surge voltage, while also addressing the issue of impedance between the power supply input and output, this invention provides a high-precision surge protection circuit, power connection line, electronic device, charging system, and high-precision surge protection method. In this circuit, the first terminal is coupled to both the power input and output terminals, and the second terminal is grounded. The circuit compares the path voltage and the trigger voltage using a surge detection module. Only when the comparison indicates a surge in the path between the power input and output terminals, the power supply module supplies power to the discharge control module. This causes the reference voltage source unit to output a reference voltage. The comparison unit performs a first processing on the reference voltage and the voltage at the second terminal of the first resistor, and outputs a corresponding first voltage to the control terminal of the discharge switch to control the conduction degree of the discharge switch, precisely clamping the voltage at the power output terminal to the set clamping voltage. When the comparison indicates no surge in the path between the power input and output terminals, the power supply module stops supplying power to the discharge control module, causing the discharge control module to stop operating and reducing circuit losses.

[0088] Please refer to Figure 1 This invention provides a high-precision surge protection circuit, whose first terminal is coupled to the power input terminal Vin and the power output terminal Vout, and whose second terminal is grounded; the high-precision surge protection circuit includes a surge detection module 10, a power module 20, a discharge control module 30, and a discharge switch Q2; the discharge control module 30 includes a reference voltage source unit 301, a comparison unit 302, a first resistor R1, and a second resistor R2;

[0089] The first terminal of the surge detection module 10, the first terminal of the first resistor R1, and the first terminal of the discharge switch Q2 are all coupled to the power input terminal Vin and the power output terminal Vout, respectively; the second terminal of the surge detection module 10 is coupled to the input terminal of the power module 20, and its third terminal is grounded; the output terminal of the power module 20 is coupled to the input terminal of the reference voltage source unit 301 and the first terminal of the comparison unit 302, respectively; the output terminal of the reference voltage source unit 301 is coupled to the first input terminal of the comparison unit 302, the second terminal of the first resistor R1 is coupled to the second input terminal of the comparison unit 302 and the first terminal of the second resistor R2, and the second terminal of the second resistor R2 is grounded; the output terminal of the comparison unit 302 is coupled to the control terminal of the discharge switch Q2, and the second terminal of the discharge switch Q2 is grounded, wherein:

[0090] The surge detection module 10 is used to compare the magnitudes of the path voltage and the trigger voltage, and only controls the power module 20 to supply power to the discharge control module 30 when the comparison result indicates that a surge has occurred in the path between the power input terminal Vin and the power output terminal Vout; otherwise, it controls the power module 20 to stop supplying power to the discharge control module 30.

[0091] The reference voltage source unit 301 is configured to output a reference voltage only when the power module 20 supplies power to the discharge control module 30; otherwise, it outputs the power ground voltage.

[0092] The comparison unit 302 is configured to:

[0093] When the power module 20 supplies power to the discharge control module 30, the reference voltage and the voltage at the second end of the first resistor R1 are processed first, and the corresponding first voltage is output to the control terminal of the discharge switch Q2 to control the conduction degree of the discharge switch Q2 and clamp the voltage at the power output terminal Vout to the clamping voltage; the first processing includes at least subtraction amplification processing.

[0094] When the power module 20 stops supplying power to the discharge control module 30, the power ground voltage is output to the control terminal of the discharge switch Q2 to control the discharge switch Q2 to turn off.

[0095] Wherein, the path voltage is the voltage on the path from the power input terminal Vin to the power output terminal Vout.

[0096] Because the first terminal of the high-precision surge protection circuit provided by this invention is coupled to the power input terminal Vin and the power output terminal Vout respectively, there is no impedance between the input and output terminals of the power line, ensuring that the circuit will not generate additional heat during normal operation and will not cause stability damage to the circuit itself; at the same time, because this invention uses a reference voltage source module, the reference voltage value will not change when the ambient temperature fluctuates, thereby ensuring the stability of the clamping voltage value, and this invention can also use the reference voltage value to set the clamping voltage value;

[0097] In one embodiment, the voltage value of the clamping voltage can be configured as follows:

[0098]

[0099] Among them, V CLAMP The clamping voltage value is V, where R1 is the resistance value of the first resistor R1, R2 is the resistance value of the second resistor R2, and V IN+ The reference voltage is the voltage value.

[0100] In one specific implementation, please refer to Figure 2 The comparison unit 302 includes an amplifier 3021, a first PMOS transistor Q1, a third resistor R3, and a first pull-down sub-unit 3022;

[0101] The power supply terminal of the amplifier 3021 is coupled to the output terminal of the power module 20, its non-inverting input terminal is coupled to the output terminal of the reference voltage source unit 301, its inverting input terminal is coupled to the second terminal of the first resistor R1, and its output terminal is coupled to the control terminal of the first PMOS transistor Q1. The source of the first PMOS transistor Q1 is coupled to the output terminal of the power module 20, and its drain is coupled to the first terminal of the first pull-down sub-unit 3022 and the first terminal of the third resistor R3, respectively. The second terminal of the first pull-down sub-unit 3022 is grounded. The second terminal of the third resistor R3 is coupled to the control terminal of the bleeder switch Q2 to output the corresponding first voltage or the power supply ground voltage. Wherein:

[0102] The amplifier 3021 is configured to:

[0103] When the power module 20 supplies power to the discharge control module 30, it compares the voltage value received at its non-inverting input terminal with the voltage value received at its inverting input terminal. If the voltage value received at its non-inverting input terminal is greater than the voltage value received at its inverting input terminal, it outputs the power supply voltage of the power module 20.

[0104] If the voltage value received at its non-inverting input terminal is less than or equal to the voltage value received at its inverting input terminal, the reference voltage and the voltage at the second terminal of the first resistor R1 are subtracted and amplified, and the corresponding second voltage value is output. The control terminal of the first PMOS transistor Q1 is used to control the conduction degree of the first PMOS transistor Q1 and clamp the voltage at the power output terminal to the clamping voltage.

[0105] The power supply voltage of the power module 20 can be understood as the power supply voltage provided by the power module 20 to the amplifier 3021.

[0106] In one specific embodiment, the discharge switch provided by the present invention can be an NMOS transistor. Of course, the present invention is not limited to this; as long as the switching of the discharge switch Q2 is controlled by the voltage at the second terminal of the third resistor R3, it is within the protection scope of the present invention.

[0107] The working principle of the amplifier 3021 provided by the present invention will now be explained.

[0108] Specifically, for an operational amplifier, if the voltage received at the non-inverting input terminal V+ is greater than the voltage received at its inverting input terminal V-, the output is the power supply voltage of the power module, which is insufficient to turn on the first PMOS transistor Q1. In this case, the gate of the discharge switch Q2 will be pulled down to 0V by the pull-down unit (the first pull-down sub-unit 3022, or the first pull-down sub-unit 3022 and the second pull-down unit 3023 described below), and naturally the voltage Vin at the power input terminal will not be discharged.

[0109] If the voltage received at its non-inverting input terminal V+ is less than the voltage received at its inverting input terminal V-, the op-amp is equivalent to working in comparator mode. The op-amp will output 0V, which will make the first PMOS transistor Q1 fully conduct, and then make the discharge switch Q2 conduct, pulling down the voltage Vin at the power input terminal, causing the voltage across the path between the power input terminal and the power output terminal to drop until V- and V+ are equal.

[0110] When the voltage received at the inverting input V- is equal to the voltage received at the non-inverting input V+, the op-amp will operate in normal mode, so that the voltage Vin at the power input is at the set value.

[0111] In one specific implementation, please refer to Figure 3 The first pull-down subunit 3022 includes a resistor.

[0112] In this case, when the power module 20 supplies power to the discharge control module 30, the first pull-down sub-unit 3022 and the PMOS transistor Q1 work together to control the gate voltage of the NMOS transistor Q2.

[0113] When the power module 20 stops supplying power to the discharge control module 30, Q1 is turned off, and the gate voltage of the NMOS transistor Q2 is pulled to the lowest potential through the first pull-down sub-unit 3022. At this time, Q2 is turned off and will not draw current from the power input terminal Vin, thereby ensuring the normal operation of the subsequent circuit.

[0114] Of course, this invention does not limit the specific implementation of the first pull-down sub-unit. For another specific implementation, please refer to... Figure 4 The first pull-down subunit 3022 includes a pull-down current source.

[0115] exist Figure 4In the example, the pull-down current source is composed of a third NMOS transistor MN3 and a fourth NMOS transistor MN4. The drain of the third NMOS transistor MN3 receives a reference current and is also coupled to its gate. The source of the third NMOS transistor MN3 is grounded, the gate of the third NMOS transistor MN3 is coupled to the gate of the fourth NMOS transistor MN4, the drain of the fourth NMOS transistor MN4 is coupled to the drain of the first PMOS transistor Q1, and the source of the fourth NMOS transistor MN4 is grounded.

[0116] certainly, Figure 4 The structure of the pull-down current source shown is merely an example; those skilled in the art can select a suitable circuit as needed.

[0117] In this case, please continue to refer to Figure 4 The comparison unit also needs to include a second pull-down subunit 3023;

[0118] The first end of the second pull-down subunit 3023 is coupled to the second end of the third resistor R3, and the second end of the second pull-down subunit 3023 is grounded.

[0119] The operating state of the second pull-down subunit is controlled by the voltage changes in the power module 20.

[0120] In one implementation, please refer to [link / reference needed]. Figure 5 The power module includes a second PMOS transistor MP2, a first capacitor C1, a fifth resistor R5, a third PMOS transistor MP3, a first NMOS transistor MN1, a second NMOS transistor MN2, a fourth PMOS transistor MP4, a sixth resistor R6, and a first diode D1.

[0121] The source and gate of the second PMOS transistor MP2 are both coupled to the second terminal of the surge detection module 10. The drain of the second PMOS transistor MP2 is coupled to the first terminal of the first capacitor C1, the first terminal of the fifth resistor R5, the gate of the third PMOS transistor MP3, and the gate of the first NMOS transistor MN1. The second terminals of the first capacitor C1 and the fifth resistor R5 are both grounded. The source of the third PMOS transistor MP3 is coupled to the gate of the second PMOS transistor MP2, and the drain of the third PMOS transistor MP3 is coupled to the first NMOS transistor MN1. The drain of the S-channel transistor MN1 and the gate of the fourth PMOS transistor MP4 are connected. The source of the first NMOS transistor MN1 is grounded. The source of the fourth PMOS transistor MP4 is coupled to the source of the second NMOS transistor MN2. The drain of the second NMOS transistor MN2 is coupled to the first terminal of the surge detection module, and its gate is coupled to the gate of the second PMOS transistor MP2. The drain of the fourth PMOS transistor MP4 is coupled to the first terminal of the sixth resistor R6 and the cathode of the first diode D1. The second terminal of the sixth resistor R6 and the anode of the first diode D1 are both grounded.

[0122] exist Figure 5 In the example, the voltage A at the positive terminal of the first diode D1 VDD This can be understood as the voltage supplied by the power module to the subsequent circuits.

[0123] Furthermore, in a specific implementation method, please refer to... Figure 6 The second pull-down submodule includes a seventh resistor R7, a third NMOS transistor MN3, and a fourth NMOS transistor MN4;

[0124] The first terminal of the seventh resistor R7 is coupled to the positive terminal of the first diode D1, and its second terminal is coupled to the drain of the third NMOS transistor MN3 and the gate of the fourth NMOS transistor MN4. The gate of the third NMOS transistor MN3 is coupled to the first terminal of the fifth resistor R5, and its source is grounded. The drain of the fourth NMOS transistor MN4 is coupled to the second terminal of the third resistor. Figure 6 (not shown in the image), its source is grounded.

[0125] In this case, when the power module 20 supplies power to the discharge control module 30, the first pull-down sub-unit 3022 and the PMOS transistor Q1 work together to control the gate voltage of the NMOS transistor Q2.

[0126] When the power module 20 stops supplying power to the discharge control module 30, Q1 is turned off, and the gate voltage of the NMOS transistor Q2 is pulled to the lowest potential through the second pull-down sub-unit 3023. At this time, Q2 is turned off and will not draw current from the power input terminal Vin, thereby ensuring the normal operation of the subsequent circuit.

[0127] Now combined Figure 7 The working process of the high-precision surge protection circuit is described below:

[0128] In practical implementation, the surge detection module includes at least one Zener diode.

[0129] exist Figure 7 In the example, the surge detection module 10 includes a first Zener diode Z1, a second Zener diode Z2, a third Zener diode Z3, a fourth resistor R4, and a fourth Zener diode Z4 connected in series.

[0130] The first end of the first Zener diode Z1 is coupled to the power input terminal Vin, the fourth Zener diode Z4 is grounded, and the first and second ends of the fourth resistor R4 are respectively coupled to the first and second input terminals of the power module 20 to output the comparison result to the power module 20.

[0131] in this case, Figure 5 The source and gate of the second PMOS transistor MP2 in the power module shown are respectively coupled to the first and second terminals of the fourth resistor R4.

[0132] In practical applications, surge voltages typically reach 50–300V. In such cases, if a surge occurs at the power input terminal Vin, the path voltage will be higher, triggering the surge detection module 10 to prevent damage to subsequent circuits. The path voltage at this time is the sum of the supply voltage and the surge voltage, where the supply voltage is the normal operating voltage provided by the power input terminal Vin. In this embodiment, the trigger voltage is the sum of the Zener voltages of the first Zener diode Z1, the second Zener diode Z2, and the third Zener diode Z3. In one example, the Zener voltages of the first Zener diode Z1, the second Zener diode Z2, the third Zener diode Z3, and the fourth Zener diode Z4 are all 6V. In practical applications, the clamping voltage of this circuit can be 25–27V.

[0133] In this situation, if current flows through the surge detection module 10, and the voltage received at the non-inverting input of the amplifier 3021 is less than or equal to the voltage received at its inverting input, the amplifier 3021 controls the conduction level of the discharge switch Q2 by controlling the conduction level of the first PMOS transistor Q1. Figure 7 In the example shown, the conduction level of the first PMOS transistor Q1 controls the gate voltage of the discharge switch Q2 to meet the discharge requirements.

[0134] Of course, the present invention does not limit the specific number of Zener diodes or the magnitude of their Zener voltage, which can be set according to the voltage value of the supply voltage and / or the voltage that the power module 20 can withstand in actual operation.

[0135] For one example, please refer to Figure 8 If the circuit is designed such that the Zener voltage of the Zener diodes is 6V, the supply voltage is less than 5V when the circuit is working normally, and the clamping voltage is 6-8V, then the surge detection module 10 can be designed to include a fourth resistor R4 and a fourth Zener diode Z4 connected in series.

[0136] In another example, please refer to Figure 9 If the circuit is designed such that the Zener voltage of the Zener diodes is 6V, the supply voltage is less than 30V when the circuit is working normally, and the clamping voltage is 33-36V, then the surge detection module 10 can be designed to include a first Zener diode Z1, a second Zener diode Z2, a third Zener diode Z3, a fourth Zener diode Z4, a fourth resistor R4, and a fifth Zener diode Z5 connected in series.

[0137] In the example above, the trigger voltage needs to be less than or equal to the clamping voltage to ensure that there is a voltage drop across the fourth resistor R4.

[0138] In other embodiments, the trigger voltage may be designed to be greater than the clamping voltage. In this case, please refer to [reference needed]. Figure 10 The power module 20 includes a second capacitor C2; the second capacitor C2 is connected in parallel with the fourth resistor R4. The voltage across the fourth resistor R4 charges the second capacitor C2, and the second capacitor C2 supplies power to the discharge control module 30.

[0139] In this case, the surge detection module 10 can be designed to include a fourth resistor R4 and a fourth Zener diode Z4 connected in series (e.g., Figure 8 Alternatively, several Zener diodes (e.g., 1000V) can be connected in series between the fourth resistor R4 and the power input terminal Vin, depending on the trigger voltage requirements. Figure 9The surge detection module 10 shown is shown.

[0140] In one example, if the circuit is designed so that the Zener voltage of the Zener diodes is 6V, the supply voltage is less than 24V when the circuit is operating normally, the trigger voltage is 30V, and the clamping voltage is 25-27V. Please refer to [reference needed]. Figure 10 Therefore, the surge detection module 10 can be designed to include a first Zener diode Z1, a second Zener diode Z2, a third Zener diode Z3, a fourth Zener diode Z4, a fourth resistor R4, and a fifth Zener diode Z5 connected in series.

[0141] Of course, when the power module 20 includes a second capacitor C2, the trigger voltage can also be designed to be less than or equal to the clamping voltage.

[0142] It should be understood that the surge in the path between the power input terminal and the power output terminal mentioned in the embodiments of the present invention can be understood as the voltage of the path between the power input terminal and the power output terminal being greater than or equal to the trigger voltage.

[0143] Furthermore, embodiments of the present invention also provide a high-precision surge protection method for... Figures 1-10 The high-precision surge protection circuit is controlled by the method comprising:

[0144] The voltage magnitudes of the path voltage and the trigger voltage are compared, and the power module 20 is controlled to supply power to the discharge control module 30 only when the comparison result indicates that a surge has occurred in the path between the power input terminal Vin and the power output terminal Vout; otherwise, the power module 20 is controlled to stop supplying power to the discharge control module 30; wherein:

[0145] If the power module 20 supplies power to the discharge control module 30, the following steps are performed:

[0146] The reference voltage source unit 301 is controlled to output a reference voltage;

[0147] The reference voltage and the voltage at the second terminal of the first resistor R1 are processed first, and the corresponding first voltage is output to the control terminal of the discharge switch Q2 to control the conduction degree of the discharge switch Q2 and clamp the voltage at the power output terminal Vout to the clamping voltage; the first processing includes at least subtraction amplification processing.

[0148] If the power module 20 stops supplying power to the discharge control module 30, the following steps are performed:

[0149] The reference voltage source unit 301 is controlled to output the power supply ground voltage;

[0150] The power supply ground voltage is output to the control terminal of the discharge switch Q2 to control the discharge switch Q2 to turn off.

[0151] For one specific implementation method, please refer to Figure 11 In practical use, the embodiments of the present invention provide the following... Figure 1 The high-precision surge protection circuit shown is controlled by the following steps.

[0152] S41: Power on;

[0153] Specifically, a voltage signal exists in the path between the power input terminal Vin and the power output terminal Vout, and the high-precision surge protection circuit operates normally.

[0154] Of course, if there is no voltage signal in the path between the power input terminal Vin and the power output terminal Vout, which is equivalent to the path voltage being less than the trigger voltage, the power module 20 will stop supplying power to the discharge control module 30.

[0155] S42: Compare the magnitudes of the path voltage and the trigger voltage. If the comparison result indicates that a surge has occurred in the path between the power input terminal Vin and the power output terminal Vout, proceed to S43; otherwise, proceed to S46.

[0156] Specifically, the surge detection module 10 compares the magnitudes of the path voltage and the trigger voltage, and only proceeds to S43 if the comparison result indicates that a surge has occurred in the path between the power input terminal Vin and the power output terminal Vout; otherwise, it proceeds to S46.

[0157] S43: Control the power module 20 to supply power to the discharge control module 30;

[0158] S44: Control the reference voltage source unit 301 to output a reference voltage;

[0159] S45: Perform a first processing on the reference voltage and the voltage at the second end of the first resistor R1, and output the corresponding first voltage to the control terminal of the discharge switch Q2 to control the conduction degree of the discharge switch Q2, clamp the voltage at the power output terminal Vout to the clamping voltage; and return to S42.

[0160] Specifically, the first process includes at least a subtraction amplification process;

[0161] S46: Control the power module 20 to stop supplying power to the discharge control module 30;

[0162] S47: Control the reference voltage source unit 301 to output the power supply ground voltage;

[0163] S48: Output the power supply ground voltage to the control terminal of the discharge switch Q2 to control the discharge switch Q2 to turn off, and return to S42.

[0164] In one specific implementation, when dealing with such Figures 1-9 When the high-precision surge protection circuit shown is used for control, the trigger voltage needs to be greater than the clamping voltage;

[0165] For example Figure 10 When the high-precision surge protection circuit shown is controlled, the trigger voltage can be less than or equal to the clamping voltage, or it can be greater than the clamping voltage.

[0166] In addition, please refer to Figure 12 The present invention also provides a power connection cable for providing a connection between a power supply device and an equipment for charging, including a voltage bus and a high-precision surge protection circuit 1 connected in parallel on the voltage bus; of course, the present invention does not limit the interface type of the connection cable, and it can also be other interfaces, such as Type A, etc.

[0167] Furthermore, embodiments of the present invention also provide an electronic device including the aforementioned high-precision surge protection circuit. As an example, the aforementioned high-precision surge protection circuit can be used as a surge protection circuit for the voltage input terminal of a chip.

[0168] Furthermore, embodiments of the present invention also provide a charging system, including the aforementioned high-precision surge protection circuit. For example, this could be a fast-charging system, or any other system requiring charging.

[0169] In summary, this embodiment of the invention compares the magnitudes of the path voltage and the trigger voltage using a surge detection module. Only when the comparison result indicates a surge in the path between the power input and power output terminals, the power module supplies power to the discharge control module. This causes the reference voltage source unit to output a reference voltage. The comparison unit performs a first processing on the reference voltage and the voltage at the second terminal of the first resistor, and outputs a corresponding first voltage to the control terminal of the discharge switch to control the conduction degree of the discharge switch, precisely clamping the voltage at the power output terminal to the set clamping voltage. When the comparison result indicates no surge in the path between the power input and power output terminals, the power module stops supplying power to the discharge control module, causing the discharge control module to stop working and reducing circuit losses.

[0170] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-precision surge protection circuit, characterized in that, Its first end is coupled to the power input terminal and the power output terminal respectively, and its second end is grounded; the high-precision surge protection circuit includes a surge detection module, a power module, a discharge control module and a discharge switch; the discharge control module includes a reference voltage source unit, a comparison unit, a first resistor and a second resistor; The first terminal of the surge detection module, the first terminal of the first resistor, and the first terminal of the discharge switch are all coupled to the power input terminal and the power output terminal, respectively. The second terminal of the surge detection module is coupled to the input terminal of the power supply module, and its third terminal is grounded; the output terminal of the power supply module is coupled to the input terminal of the reference voltage source unit and the first terminal of the comparison unit, respectively. The output terminal of the reference voltage source unit is coupled to the first input terminal of the comparator unit. The second terminal of the first resistor is coupled to both the second input terminal of the comparator unit and the first terminal of the second resistor. The second terminal of the second resistor is grounded. The output terminal of the comparator unit is coupled to the control terminal of the bleeder switch. The second terminal of the bleeder switch is grounded. The surge detection module is used to compare the magnitudes of the path voltage and the trigger voltage, and only controls the power module to supply power to the discharge control module when the comparison result indicates that a surge has occurred in the path between the power input terminal and the power output terminal; otherwise, it controls the power module to stop supplying power to the discharge control module. The reference voltage source unit is configured to output a reference voltage only when the power module supplies power to the discharge control module; otherwise, it outputs the power ground voltage. The comparison unit is configured to: When the power module supplies power to the discharge control module, the reference voltage and the voltage at the second end of the first resistor are processed first, and the corresponding first voltage is output to the control terminal of the discharge switch to control the conduction degree of the discharge switch and clamp the voltage at the power output terminal to the clamping voltage; the first processing includes at least subtraction amplification processing. When the power module stops supplying power to the discharge control module, the power supply ground voltage is output to the control terminal of the discharge switch to control the discharge switch to turn off.

2. The high-precision surge protection circuit according to claim 1, characterized in that, The clamping voltage value is configured as follows: Among them, V CLAMP The clamping voltage value is V, where R1 is the resistance value of the first resistor, R2 is the resistance value of the second resistor, and V is the clamping voltage value. IN+ The reference voltage is the voltage value.

3. The high-precision surge protection circuit according to claim 2, characterized in that, The comparison unit includes an amplifier, a first PMOS transistor, a third resistor, and a first pull-down sub-unit; The amplifier's power supply terminal is coupled to the output terminal of the power module, its non-inverting input terminal is coupled to the output terminal of the reference voltage source unit, its inverting input terminal is coupled to the second terminal of the first resistor, its output terminal is coupled to the control terminal of the first PMOS transistor, the source of the first PMOS transistor is coupled to the output terminal of the power module, and its drain is coupled to the first terminal of the first pull-down subunit and the first terminal of the third resistor, respectively. The second terminal of the first pull-down subunit is grounded; the second terminal of the third resistor is coupled to the control terminal of the bleeder switch to output the corresponding first voltage or the power supply ground voltage; wherein: The amplifier is configured to: When the power module supplies power to the discharge control module, it compares the voltage value received at its non-inverting input terminal with the voltage value received at its inverting input terminal. If the voltage value received at its non-inverting input terminal is greater than the voltage value received at its inverting input terminal, it outputs the power supply voltage of the power module. If the voltage value received at its non-inverting input terminal is less than or equal to the voltage value received at its inverting input terminal, the reference voltage and the voltage at the second terminal of the first resistor are subtracted and amplified, and the corresponding second voltage value is output. The control terminal of the first PMOS transistor controls the conduction degree of the first PMOS transistor and clamps the voltage at the power output terminal to the clamping voltage.

4. The high-precision surge protection circuit according to claim 3, characterized in that, The discharge switch is an NMOS transistor.

5. The high-precision surge protection circuit according to claim 3, characterized in that, The first pull-down sub-unit includes a resistor.

6. The high-precision surge protection circuit according to claim 3, characterized in that, The power module includes a second PMOS transistor, a first capacitor, a fifth resistor, a third PMOS transistor, a first NMOS transistor, a second NMOS transistor, a fourth PMOS transistor, a sixth resistor, and a first diode; The source and gate of the second PMOS transistor are both coupled to the second terminal of the surge detection module. The drain of the second PMOS transistor is coupled to the first terminal of the first capacitor, the first terminal of the fifth resistor, the gate of the third PMOS transistor, and the gate of the first NMOS transistor. The second terminal of the first capacitor and the second terminal of the fifth resistor are both grounded. The source of the third PMOS transistor is coupled to the gate of the second PMOS transistor. The drain of the third PMOS transistor is coupled to the drain of the first NMOS transistor and the gate of the fourth PMOS transistor. The source of the first NMOS transistor is grounded. The source of the fourth PMOS transistor is coupled to the source of the second NMOS transistor. The drain of the second NMOS transistor is coupled to the first terminal of the surge detection module, and its gate is coupled to the gate of the second PMOS transistor. The drain of the fourth PMOS transistor is coupled to the first terminal of the sixth resistor and the cathode of the first diode. The second terminal of the sixth resistor and the anode of the first diode are both grounded.

7. The high-precision surge protection circuit according to claim 6, characterized in that, The first pull-down sub-unit includes a pull-down current source.

8. The high-precision surge protection circuit according to claim 7, characterized in that, The comparison unit further includes a second pull-down subunit; The first end of the second pull-down subunit is coupled to the second end of the third resistor, and the second end of the second pull-down subunit is grounded.

9. The high-precision surge protection circuit according to claim 8, characterized in that, The second pull-down submodule includes a seventh resistor, a third NMOS transistor, and a fourth NMOS transistor; The first end of the seventh resistor is coupled to the positive terminal of the first diode, and its second end is coupled to the drain of the third NMOS transistor and the gate of the fourth NMOS transistor. The gate of the third NMOS transistor is coupled to the first end of the fifth resistor, and its source is grounded. The drain of the fourth NMOS transistor is coupled to the second end of the third resistor, and its source is grounded.

10. The high-precision surge protection circuit according to claim 1, characterized in that, The surge detection module includes a first Zener diode, a second Zener diode, a third Zener diode, a fourth resistor, and a fourth Zener diode connected in series. The first end of the first Zener diode is coupled to the power input terminal, the fourth Zener diode is grounded, and the first and second ends of the fourth resistor are respectively coupled to the first and second input terminals of the power module to output the comparison result to the power module.

11. The high-precision surge protection circuit according to claim 10, characterized in that, The trigger voltage is the sum of the Zener voltage of the first Zener diode, the Zener voltage of the second Zener diode, the Zener voltage of the third Zener diode, and the Zener voltage of the fourth Zener diode.

12. The high-precision surge protection circuit according to claim 11, characterized in that, The trigger voltage is greater than the clamping voltage.

13. The high-precision surge protection circuit according to claim 11, characterized in that, The trigger voltage is less than or equal to the clamping voltage.

14. The high-precision surge protection circuit according to claim 13, characterized in that, The power module includes a second capacitor; the second capacitor is connected in parallel with the fourth resistor.

15. A power connection cable for providing a charging connection between a power supply device and an equipment, characterized in that, Includes a voltage bus and a high-precision surge protection circuit as described in any one of claims 1-14 connected in parallel to the voltage bus.

16. An electronic device, characterized in that, Includes the high-precision surge protection circuit as described in any one of claims 1-14.

17. A charging system, characterized in that, It includes a power supply device and the electronic device as described in claim 16.

Images