Overvoltage and overcurrent self-locking protection circuit

Abstract

The invention discloses an overvoltage and overcurrent self-locking protection circuit, which is connected between a power supply side and a power utilization side, and comprises a switch module usedfor switching on or switching off the conductive connection between the power supply side and the power utilization side, a self-locking unit configured to drive the switch module to disconnect the conductive connection between the power supply side and the power utilization side when the power supply side outputs overcurrent or overvoltage and locking the disconnected state of the switch module until the switch module is electrified again when the power supply side outputs overcurrent or overvoltage. The invention discloses an overvoltage and overcurrent self-locking protection circuit. Whenoutput overvoltage or output overcurrent occurs on the power supply side, the self-locking protection unit locks the switch module and completely disconnects the conductive connection between the power supply side and the power utilization side until power on again, so that the power utilization side is prevented from repeatedly bearing high current and high voltage for a short time, and timely and reliable power utilization protection is provided for equipment on the power utilization side.

Description

technical field [0001] The invention relates to the technical field of power electronics, in particular to an overvoltage and overcurrent self-locking protection circuit. Background technique [0002] The application of electronic products in today's society can be said to be indispensable in our daily life, and these electronic products need to be powered by DC power supply, but when using DC power supply, once the power supply is abnormal or the cold start occurs instantly Voltage, or due to load short circuit, or load overload, etc., will generate overcurrent, causing permanent damage to the back-end components and equipment of the power supply, burning components or equipment in light cases, and causing fires in severe cases, causing serious personal safety and property damage. loss. In view of the above problems, an overcurrent and overvoltage protection circuit is usually added to the power supply circuit to improve the safety performance of the circuit. [0003] Mos...

AI Technical Summary

Problems solved by technology

[0003] Traditional overvoltage and overcurrent protection mostly uses a combination of a voltage regulator tube and a PTC thermistor, and the overvoltage and overcurrent protection is imprecise, poor in consistency, and poor in protection effect

At present, the existing integrated power supply protection chips on the market have the advantages of high integration and small size, but the protection range of the power supply voltage is generally narrow, and limited by the small size of the chip, the working current is very small, so it cannot be used for current protection. Applications for larger occasions

[0004] In addition, most protection circuits or protection chips do not have protection self-locking function. When the output end is turned off, the circuit will resume working. When the protection circuit detects the existence of overvoltage or overcurrent, it will turn off the output again. so repeatedly

Although this solution can prevent the electronic equipment at the output end from working in the overvoltage and overcurrent state for a long time, it cannot completely disconnect the connection between the output end of the power supply and the power consumption end, so that the power consumption end still needs to repeatedly withstand high current and high voltage for a short period of time. Voltage, resulting in the electrical terminal electronic equipment is easily damaged

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