Quick turn-off electronic safety circuit

Abstract

The utility model discloses a fast turn-off electronic safety circuit in the field of electronic safety, which comprises a current sampling circuit, an electronic turn-off circuit, a drive control circuit and a current turn-off control circuit, the output end of the current sampling circuit is connected with the input end of the driving control circuit and the input end of the current turn-off control circuit, and the output end of the driving control circuit and the output end of the current turn-off control circuit are connected with the driving end of the electronic turn-off circuit. And the output end of the electronic disconnection circuit is connected with the output voltage. According to the utility model, the problem that the conventional slow-melting safety device cannot be disconnected within the fusing time and is easy to cause the combustion of the post-stage continuous large current is solved, the post-stage circuit can be quickly cut off, the effect of quickly cutting off the safety is realized, the combustion accident caused by the post-stage continuous large current is further avoided, and the safety accident is prevented.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic insurance, in particular to a fast-shutdown electronic insurance circuit. Background Art

[0002] In the power conversion power supply of the switching power supply, such as the DC-DC switching power supply, the rated current of the fuse connected in series at the input end is often relatively large due to the low input voltage and large input current. Therefore, in order to protect these power supplies from damage caused by overcurrent, a fuse is usually connected in series at the input end. Due to the requirements of surge current, this type of fuse usually uses a slow-blow fuse, such as a 50A or 100A fuse, which will blow when the current exceeds twice its rated current, and the blowing time is between 2 seconds and 60 seconds.

[0003] However, during the fuse time of the above-mentioned insurance, devices such as the devices in the subsequent circuit and the power MOS tube are prone to abnormal short-circuit failure, which is equivalent to a short circuit between the positive and negative poles of the input. Especially when the input source is large or equipped with a battery input, the short-circuit current can instantly reach 200A or more (although the time is very short, only 2 milliseconds). In this case, the slow-blow insurance device at the input end cannot be disconnected within this time, so it cannot effectively protect the circuit; in addition, some devices with lower temperature resistance, such as PCB (FR-4 board, TG value is 150℃), will reach the ignition point due to the instantaneous excessive current and sudden temperature rise, causing combustion and leading to safety failures.

[0004] The above defects need to be solved urgently. Utility Model Content

[0005] In order to solve the problem that the existing slow-blow fuse device cannot be disconnected within its fusing time, which easily causes the subsequent stage to burn due to continuous large current, the utility model provides a fast-shutdown electronic fuse circuit.

[0006] The technical solution of the utility model is as follows:

[0007] A fast-shutdown electronic insurance circuit comprises a current sampling circuit, an electronic disconnection circuit, a drive control circuit and a current disconnection control circuit, wherein the input end of the current sampling circuit is connected to an input voltage, the output end of the current sampling circuit is respectively connected to the input end of the drive control circuit and the input end of the current disconnection control circuit, the output end of the drive control circuit and the output end of the current disconnection control circuit are both connected to the drive end of the electronic disconnection circuit, and the output end of the electronic disconnection circuit is connected to the output voltage.

[0008] According to the above scheme of the utility model, the current shutdown control circuit includes a current amplification circuit and a current comparison circuit, the input end of the current amplification circuit is connected to the input voltage, the output end of the current amplification circuit is connected to the input end of the current comparison circuit, and the output end of the current comparison circuit is connected to the driving end of the electronic disconnection circuit.

[0009] Furthermore, the current amplifier circuit includes a capacitor C218, a capacitor C219, a resistor R472, a resistor R474, a capacitor C216, a chip U30, and a capacitor C229. The input voltage is respectively connected to one end of the capacitor C218 and one end of the resistor R472. The other end of the resistor R472 is respectively connected to one end of the capacitor C216 and the first pin of the chip U30. The other end of the capacitor C216 is respectively connected to one end of the resistor R474 and the first pin of the chip U30. The second pin of the chip U30 is connected, the other end of the resistor R474 is connected to one end of the capacitor C219, the other end of the capacitor C219 and the other end of the capacitor C218 are both grounded, the seventh pin of the chip U30 is connected to one end of the capacitor C229, the other end of the capacitor C229, the third pin of the chip U30, the fourth pin of the chip U30, and the fifth pin of the chip U30 are all grounded, and the seventh pin of the chip U30 is connected to the input end of the current comparison circuit.

[0010] According to the utility model of the above scheme, the current comparison circuit includes a resistor R480, a resistor R5, a capacitor C234, a capacitor C1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a comparator U21, a capacitor C254, a resistor R6, a capacitor C248, a resistor R493, a transistor Q102, a resistor R471, a resistor R455, and a MOS tube Q101. One end of the resistor R480 is connected to the output end of the current amplifier circuit, and the other end of the resistor R480 is respectively connected to one end of the resistor R2, the first pin of the comparator U21, one end of the capacitor C234, and one end of the resistor R5. The other end of the resistor R2 is respectively connected to the fourth pin of the comparator U21 and one end of the resistor R6. The other end of the capacitor C234 and the other end of the resistor R5 are both grounded. The second pin of the comparator U21 is respectively connected to one end of the resistor R3, one end of the resistor R4, and one end of the capacitor C1. One end of the resistor R4 is connected, the other end of the resistor R4 and the other end of the capacitor C1 are both grounded, the other end of the resistor R3 is respectively connected to the 5th pin of the comparator U21 and one end of the capacitor C254, the other end of the capacitor C254 and the 3rd pin of the comparator U21 are both grounded, the other end of the resistor R6 is respectively connected to one end of the capacitor C248, one end of the resistor R493, and the B pole of the transistor Q102, the other end of the capacitor C248, the other end of the resistor R493, and the E pole of the transistor Q102 are all grounded, the C pole of the transistor Q102 is connected to one end of the resistor R471, the other end of the resistor R471 is respectively connected to the G pole of the MOS tube Q101 and one end of the resistor R455, the S pole of the MOS tube Q101 and the other end of the resistor R455 are both connected to the driving end of the electronic disconnection circuit, and the D pole of the MOS tube Q101 is connected to the output voltage.

[0011] Furthermore, the transistor Q102 is an NPN transistor.

[0012] According to the above-mentioned solution of the utility model, the MOS tube Q101 is of P-channel depletion type.

[0013] According to the utility model of the above scheme, the current sampling circuit includes a sampling resistor RS1, one end of the sampling resistor RS1 is connected to the input voltage, and the other end of the sampling resistor RS1 is respectively connected to the input end of the drive control circuit and the input end of the current shutdown control circuit.

[0014] According to the utility model of the above scheme, the drive control circuit includes a resistor R382, a resistor R390, a capacitor C204, a resistor R411, a capacitor C195, a resistor R406, a chip U26, a resistor R436, and a capacitor C192. One end of the resistor R382 and one end of the resistor R390 are connected to the input end of the current sampling circuit, and the other end of the resistor R382 is respectively connected to one end of the capacitor C204, one end of the resistor R411, and the third pin of the chip U26. The other end of the resistor R390 is respectively connected to the second pin of the chip U26 and one end of the capacitor C195. The other end of the capacitor C204 and the capacitor C195 are respectively connected. The other end of the resistor R411, the other end of the capacitor C195, the 4th pin of the chip U26, and the 5th pin of the chip U26 are all grounded, the 1st pin of the chip U26 is connected to one end of the resistor R406, the other end of the resistor R406 is connected to the output end of the current sampling circuit, the 6th pin of the chip U26 is connected to one end of the capacitor C192, the 7th pin of the chip U26 is connected to one end of the resistor R436, the other end of the capacitor C192 and the other end of the resistor R436 are all grounded, and the 10th pin of the chip U26 is respectively connected to the input end of the electronic disconnection circuit and the output end of the current shutdown control circuit.

[0015] According to the utility model of the above scheme, the electronic disconnection circuit includes a diode D30, a resistor R420, a resistor R421, and a MOS tube Q97, one end of the diode D30 is respectively connected to the output end of the drive control circuit, the output end of the current shutdown control circuit, and one end of the resistor R420, the other end of the diode D30 is connected to one end of the resistor R421, the other end of the resistor R420 and the other end of the resistor R421 are both connected to the G pole of the MOS tube Q97, the D pole of the MOS tube Q97 is connected to the output end of the current sampling circuit, and the S pole of the MOS tube Q97 is connected to the output voltage.

[0016] Furthermore, the MOS transistor Q97 is of N-channel depletion type.

[0017] The utility model according to the above scheme has the following beneficial effects:

[0018] In the above-mentioned fast-shutdown electronic insurance circuit, when the current value flowing through the current sampling circuit is less than the set threshold, the drive control circuit drives the electronic disconnect circuit to work normally, thereby supplying power to the subsequent circuit; when the current value flowing through the current sampling circuit reaches the set threshold, the current shutdown control circuit can quickly shut down the electronic disconnect circuit, thereby quickly cutting off the subsequent circuit, achieving the purpose of disconnecting the power loop current, and realizing the role of quickly cutting off the insurance, thereby avoiding the occurrence of burning accidents when the subsequent current continues to be large, and preventing safety accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a circuit diagram of the utility model;

[0020] Figure 2 A circuit diagram of the utility model;

[0021] Figure 3 is a circuit diagram of a current sampling circuit;

[0022] Figure 4 A circuit diagram of a drive control circuit;

[0023] Figure 5 is a circuit diagram of a current cut-off control circuit;

[0024] Figure 6 is a circuit diagram of a current amplifier circuit;

[0025] Figure 7 is a circuit diagram of a current comparison circuit;

[0026] Figure 8 Circuit diagram for electronic disconnect circuit. DETAILED DESCRIPTION

[0027] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0028] like Figure 1 , Figure 2 As shown, the utility model provides a fast-shutdown electronic insurance circuit, a current sampling circuit, an electronic disconnect circuit, a drive control circuit, and a current disconnect control circuit. The input end of the current sampling circuit is connected to the input voltage, the output end of the current sampling circuit is respectively connected to the input end of the drive control circuit and the input end of the current disconnect control circuit, the output end of the drive control circuit and the output end of the current disconnect control circuit are both connected to the drive end of the electronic disconnect circuit, and the output end of the electronic disconnect circuit is connected to the output voltage.

[0029] like Figure 3 As shown, in this embodiment, the current sampling circuit includes a sampling resistor RS1, one end of the sampling resistor RS1 is connected to the input voltage, and the other end of the sampling resistor RS1 is respectively connected to the input end of the drive control circuit and the input end of the current shutdown control circuit. The current sampling circuit is used to detect the current value flowing into the electronic disconnection device loop. When current flows through the sampling resistor RS1, a certain voltage drop will be generated on the sampling resistor RS1, and a driving voltage will be generated for the drive control circuit, thereby driving the electronic disconnection circuit. Of course, the sampling resistor RS1 can also be replaced by a shunt, a current transformer, a Hall element and other devices. In actual design, the composition of the current sampling circuit can be designed according to actual conditions.

[0030] like Figure 4 As shown, in this embodiment, the drive control circuit includes a resistor R382, a resistor R390, a capacitor C204, a resistor R411, a capacitor C195, a resistor R406, a chip U26, a resistor R436, and a capacitor C192. One end of the resistor R382 and one end of the resistor R390 are connected to one end of the sampling resistor RS1, and the other end of the resistor R382 is respectively connected to one end of the capacitor C204, one end of the resistor R411, and the third pin of the chip U26. The other end of the resistor R390 is respectively connected to the second pin of the chip U26 and one end of the capacitor C195. The other end of the capacitor C204, The other end of the resistor R411, the other end of the capacitor C195, the 4th pin of the chip U26, and the 5th pin of the chip U26 are all connected to the ground, the 1st pin of the chip U26 is connected to one end of the resistor R406, the other end of the resistor R406 is connected to the other end of the sampling resistor RS1, the 6th pin of the chip U26 is connected to one end of the capacitor C192, the 7th pin of the chip U26 is connected to one end of the resistor R436, the other end of the capacitor C192 and the other end of the resistor R436 are all connected to the ground, and the 10th pin of the chip U26 is respectively connected to the driving end of the electronic disconnection circuit and the output end of the current shutdown control circuit. When current flows through the sampling resistor RS1, a certain voltage drop will be generated on the sampling resistor RS1, and the chip U26 executes the voltage across the sampling resistor RS1, so that the 10th pin of the chip U26 generates a driving voltage, thereby driving the electronic disconnection circuit to work normally.

[0031] like Figure 5 As shown, in this embodiment, the current shutdown control circuit includes a current amplification circuit and a current comparison circuit. The input end of the current amplification circuit is connected to the input voltage, the output end of the current amplification circuit is connected to the input end of the current comparison circuit, and the output end of the current comparison circuit is connected to the driving end of the electronic disconnection circuit.

[0032] like Figure 6As shown, in this embodiment, the current amplification circuit includes capacitor C218, capacitor C219, resistor R472, resistor R474, capacitor C216, chip U30, and capacitor C229. The input voltage is respectively connected to one end of capacitor C218 and one end of resistor R472. The other end of resistor R472 is respectively connected to one end of capacitor C216 and the first pin of chip U30. The other end of capacitor C216 is respectively connected to one end of resistor R474 and the second pin of chip U30. The other end of resistor R474 is connected to one end of capacitor C219. The other end of capacitor C219 and the other end of capacitor C218 are both grounded. The seventh pin of chip U30 is connected to one end of capacitor C229. The other end of capacitor C229, the third pin of chip U30, the fourth pin of chip U30, and the fifth pin of chip U30 are all grounded. The seventh pin of chip U30 is connected to the input end of the current comparison circuit. The current sampled by the sampling resistor RS1 is amplified through the chip U30, the resistor R472, the resistor R474, the capacitor C218, the capacitor C219, the capacitor C216, and the capacitor C229, and then the current is transmitted to the current comparison circuit, which compares the current value with the set current threshold.

[0033] like Figure 7As shown, in this embodiment, the current comparison circuit includes a resistor R480, a resistor R5, a capacitor C234, a capacitor C1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a comparator U21, a capacitor C254, a resistor R6, a capacitor C248, a resistor R493, a transistor Q102, a resistor R471, a resistor R455, and a MOS tube Q101. One end of the resistor R480 is connected to the seventh pin of the chip U30, and the other end of the resistor R480 is respectively connected to one end of the resistor R2, the first pin of the comparator U21, one end of the capacitor C234, and one end of the resistor R5. The other end of the resistor R2 is respectively connected to the fourth pin of the comparator U21 and one end of the resistor R6. The other end of the capacitor C234 and the other end of the resistor R5 are both grounded. The second pin of the comparator U21 is respectively connected to one end of the resistor R3 and one end of the resistor R4. , and one end of the capacitor C1, the other end of the resistor R4 and the other end of the capacitor C1 are both grounded, the other end of the resistor R3 is respectively connected to the 5th pin of the comparator U21 and one end of the capacitor C254, the other end of the capacitor C254 and the 3rd pin of the comparator U21 are both grounded, the other end of the resistor R6 is respectively connected to one end of the capacitor C248, one end of the resistor R493, and the B pole of the transistor Q102, the other end of the capacitor C248, the other end of the resistor R493, and the E pole of the transistor Q102 are all grounded, the C pole of the transistor Q102 is connected to one end of the resistor R471, the other end of the resistor R471 is respectively connected to the G pole of the MOS tube Q101 and one end of the resistor R455, the S pole of the MOS tube Q101 and the other end of the resistor R455 are both connected to the electronic disconnection circuit, and the D pole of the MOS tube Q101 is connected to the output voltage. The current sampled and amplified by the current amplifier circuit is compared with the first pin and the second pin of the comparator U21. When the current reaches the set threshold, the first pin of the comparator U21 outputs a high level, so that the transistor Q102 is turned on, thereby turning on the MOS tube Q101, and the circuit can be quickly electronically disconnected, thereby achieving the purpose of disconnecting the power loop current. In addition, the transistor Q102 is an NPN transistor, and the MOS tube Q101 is a P-channel depletion type. Of course, in actual design, the models of the transistor Q102 and the MOS tube Q101 can be designed according to actual conditions.

[0034] like Figure 8As shown, in this embodiment, the electronic disconnection circuit includes a diode D30, a resistor R420, a resistor R421, and a MOS tube Q97. One end of the diode D30 is respectively connected to the 10th pin of the chip U26, the S pole of the MOS tube Q101, the other end of the resistor R455, and one end of the resistor R420. The other end of the diode D30 is connected to one end of the resistor R421. The other end of the resistor R420 and the other end of the resistor R421 are both connected to the G pole of the MOS tube Q97. The D pole of the MOS tube Q97 is connected to the other end of the resistor R406 and the other end of the sampling resistor RS1. The S pole of the MOS tube Q97 is connected to the output voltage. When the current value flowing through the current sampling circuit is less than the set threshold, the drive control circuit drives the MOS tube Q97 to turn on, thereby supplying power to the subsequent circuit; when the current flowing through the current sampling circuit reaches the set threshold, the first pin of the comparator U21 outputs a high level, so that the triode Q102 is turned on, thereby turning on the MOS tube Q101, and quickly turning off the drive of the MOS tube Q97 to disconnect the current device in the loop. In addition, the MOS tube Q97 is an N-channel depletion type. Of course, in actual design, the model of the MOS tube Q97 can be designed according to actual conditions.

[0035] When the utility model is in use, when current flows through the sampling resistor RS1, a certain voltage drop will be generated on the sampling resistor RS1, and the chip U26 executes the voltage across the sampling resistor RS1, so that the 10th pin of the chip U26 generates a driving voltage to control the MOS tube Q97 in the electronic disconnection circuit. When the current value flowing through the sampling resistor RS1 is less than the set threshold, the current value is a safe current value, and the MOS tube Q97 is turned on to supply power to the subsequent circuit; when the current flowing through the current sampling circuit reaches the set threshold, the current sampling of the sampling resistor RS1 is amplified by the current amplifier circuit, and then compared with the first pin and the second pin of the comparator U21. When this current reaches the set threshold, the first pin of the comparator U21 outputs a high level, so that the triode Q102 is turned on, thereby turning on the MOS tube Q101, and then turning on the MOS tube Q101, quickly turning off the drive of the MOS tube Q97, and quickly cutting off the subsequent circuit, achieving the purpose of disconnecting the power loop current, and realizing the role of quickly cutting off the insurance, thereby avoiding the accident of burning when the subsequent current continues to be large, and preventing safety accidents.

[0036] It should be understood that those skilled in the art can make improvements or changes based on the above description, and all these improvements and changes should fall within the scope of protection of the claims attached to the utility model.

[0037] The above is an exemplary description of the utility model patent in conjunction with the accompanying drawings. It is obvious that the implementation of the utility model patent is not limited to the above-mentioned method. As long as various improvements are made by adopting the method concept and technical solution of the utility model patent, or the concept and technical solution of the utility model patent are directly applied to other occasions without improvement, they are all within the protection scope of the utility model.

Claims

1. A fast-shutdown electronic insurance circuit, characterized in that: It includes a current sampling circuit, an electronic disconnection circuit, a drive control circuit, and a current shutdown control circuit. The input end of the current sampling circuit is connected to the input voltage, the output end of the current sampling circuit is respectively connected to the input end of the drive control circuit and the input end of the current shutdown control circuit, the output end of the drive control circuit and the output end of the current shutdown control circuit are both connected to the drive end of the electronic disconnection circuit, and the output end of the electronic disconnection circuit is connected to the output voltage.

2. The fast-shutdown electronic safety circuit according to claim 1, characterized in that: The current shutdown control circuit includes a current amplifying circuit and a current comparing circuit. The input end of the current amplifying circuit is connected to the input voltage, the output end of the current amplifying circuit is connected to the input end of the current comparing circuit, and the output end of the current comparing circuit is connected to the driving end of the electronic disconnection circuit.

3. The fast-shutdown electronic safety circuit according to claim 2, characterized in that: The current amplification circuit includes capacitor C218, capacitor C219, resistor R472, resistor R474, capacitor C216, chip U30, and capacitor C229. The input voltage is respectively connected to one end of the capacitor C218 and one end of the resistor R472. The other end of the resistor R472 is respectively connected to one end of the capacitor C216 and the first pin of the chip U30. The other end of the capacitor C216 is respectively connected to one end of the resistor R474 and the second pin of the chip U30. The other end of the resistor R474 is connected to one end of the capacitor C219. The other end of the capacitor C219 and the other end of the capacitor C218 are both grounded. The seventh pin of the chip U30 is connected to one end of the capacitor C229. The other end of the capacitor C229, the third pin of the chip U30, the fourth pin of the chip U30, and the fifth pin of the chip U30 are all grounded. The seventh pin of the chip U30 is connected to the input end of the current comparison circuit.

4. The fast-shutdown electronic safety circuit according to claim 2, characterized in that: The current comparison circuit includes a resistor R480, a resistor R5, a capacitor C234, a capacitor C1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a comparator U21, a capacitor C254, a resistor R6, a capacitor C248, a resistor R493, a transistor Q102, a resistor R471, a resistor R455, and a MOS tube Q101. One end of the resistor R480 is connected to the output end of the current amplifier circuit. The other end of the resistor R480 is respectively connected to one end of the resistor R2, the first pin of the comparator U21, one end of the capacitor C234, and one end of the resistor R5. The other end of the resistor R2 is respectively connected to the fourth pin of the comparator U21 and one end of the resistor R6. The other end of the capacitor C234 and the other end of the resistor R5 are both grounded. The second pin of the comparator U21 is respectively connected to one end of the resistor R3, one end of the resistor R4, and one end of the capacitor C1. The other end of the resistor R4 and the other end of the capacitor C1 are both grounded, the other end of the resistor R3 is respectively connected to the 5th pin of the comparator U21 and one end of the capacitor C254, the other end of the capacitor C254 and the 3rd pin of the comparator U21 are both grounded, the other end of the resistor R6 is respectively connected to one end of the capacitor C248, one end of the resistor R493, and the B pole of the transistor Q102, the other end of the capacitor C248, the other end of the resistor R493, and the E pole of the transistor Q102 are all grounded, the C pole of the transistor Q102 is connected to one end of the resistor R471, the other end of the resistor R471 is respectively connected to the G pole of the MOS tube Q101 and one end of the resistor R455, the S pole of the MOS tube Q101 and the other end of the resistor R455 are both connected to the driving end of the electronic disconnection circuit, and the D pole of the MOS tube Q101 is connected to the output voltage.

5. The fast-shutdown electronic safety circuit according to claim 4, characterized in that: The transistor Q102 is an NPN transistor.

6. The fast-shutdown electronic safety circuit according to claim 4, characterized in that: The MOS transistor Q101 is of P-channel depletion type.

7. The fast-shutdown electronic safety circuit according to claim 1, characterized in that: The current sampling circuit includes a sampling resistor RS1 , one end of the sampling resistor RS1 is connected to the input voltage, and the other end of the sampling resistor RS1 is respectively connected to the input end of the drive control circuit and the input end of the current shutdown control circuit.

8. The fast-shutdown electronic safety circuit according to claim 1, characterized in that: The drive control circuit includes a resistor R382, a resistor R390, a capacitor C204, a resistor R411, a capacitor C195, a resistor R406, a chip U26, a resistor R436, and a capacitor C192. One end of the resistor R382 and one end of the resistor R390 are connected to the input end of the current sampling circuit. The other end of the resistor R382 is respectively connected to one end of the capacitor C204, one end of the resistor R411, and the third pin of the chip U26. The other end of the resistor R390 is respectively connected to the second pin of the chip U26 and one end of the capacitor C195. The other end of the capacitor C204 and the other end of the resistor R411 are respectively connected to the input end of the current sampling circuit. One end, the other end of the capacitor C195, the 4th pin of the chip U26, and the 5th pin of the chip U26 are all grounded, the 1st pin of the chip U26 is connected to one end of the resistor R406, and the other end of the resistor R406 is connected to the output end of the current sampling circuit, the 6th pin of the chip U26 is connected to one end of the capacitor C192, the 7th pin of the chip U26 is connected to one end of the resistor R436, the other end of the capacitor C192 and the other end of the resistor R436 are both grounded, and the 10th pin of the chip U26 is respectively connected to the input end of the electronic disconnect circuit and the output end of the current shutdown control circuit.

9. The fast-shutdown electronic safety circuit according to claim 1, characterized in that: The electronic disconnection circuit includes a diode D30, a resistor R420, a resistor R421, and a MOS tube Q97. One end of the diode D30 is respectively connected to the output end of the drive control circuit, the output end of the current shutdown control circuit, and one end of the resistor R420. The other end of the diode D30 is connected to one end of the resistor R421. The other end of the resistor R420 and the other end of the resistor R421 are both connected to the G pole of the MOS tube Q97. The D pole of the MOS tube Q97 is connected to the output end of the current sampling circuit. The S pole of the MOS tube Q97 is connected to the output voltage.

10. The fast-shutdown electronic safety circuit according to claim 9, characterized in that: The MOS transistor Q97 is of N-channel depletion type.

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