short circuit protection circuit

Abstract

A short-circuit protection circuit, coupled to an output adjustment circuit, includes a short-circuit detection module, a counting module, and a first signal generation module and a second signal generation module that are not interlocked with soft start. Wherein, when the short-circuit detection module detects that the output of the output adjustment circuit is in a short-circuit state, it sends a short-circuit signal, and the short-circuit signal makes the counting module count through the first clock cycle, and sends information to make the first signal generating module Sending a dormancy start signal to make the output adjustment circuit stop outputting, and when the first signal generating module sends out the dormancy start signal, the dormancy start signal makes the counting module count through the second clock cycle, and then the second signal occurs The module sends out a dormancy end signal to make the output adjustment circuit restart output.

Description

technical field [0001] The invention relates to a short circuit protection circuit, in particular to a short circuit protection circuit with hiccup mode. Background technique [0002] In today's market, high-current DC-DC switching power supplies are widely used. However, once a short-circuit accident occurs in the system using this power supply, it may cause safety accidents due to excessive temperature rise. Short circuit protection circuit to improve product reliability. [0003] Currently known short-circuit protection circuits mainly use two methods, one of which is foldback current limiting, which takes the output current limit of the switching power supply as the control target, but this method of short-circuit protection circuit has disadvantages, including not having Thorough automatic recovery capability, and because the current limit threshold cannot be lowered without limit, it cannot greatly reduce short-circuit consumption and so on. Another better way is the...

AI Technical Summary

Problems solved by technology

[0004] This kind of hiccup mode still has two main disadvantages. One is that when a short circuit occurs, it must go through a soft-start period of current-limiting working state before entering sleep, and the soft-start period is usually on the order of milliseconds. The switching power supply system will suffer huge power consumption during the period of current-limiting working state, and will accelerate aging. Another disadvantage is that the soft-start cycle is the minimum unit of the sleep time. Extending the sleep time can reduce the power consumption during short-circuit , but it will also lengthen the response time of short circuit recovery

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