A power switch protection circuit and protection method

Abstract

The present invention provides a power switch protection circuit and protection method, which can: detect the temperature of the surrounding environment of the electric control switch through the thermistor R2; when the PG signal output by the hot plug circuit is at a low level: When the resistance value drops due to the increase of the external temperature and triggers the low threshold of the Schmitt trigger circuit, the Schmitt trigger circuit is controlled to output a low level; the resistance value of the thermistor R2 decreases due to the increase of the external temperature but does not cause When the low threshold of the Schmitt trigger circuit is triggered, the Schmitt trigger circuit is controlled to output a high level; through the high and low levels output by the Schmitt trigger circuit, the MOSFET tube Q1 is controlled to be turned on and off, and then the electric control switch is controlled. The on-off of the control terminal; when the PG signal output by the hot-swap circuit is at a high level, the resistance change of R2 is invalid for the level signal output control of the Schmitt trigger circuit, and the Schmitt trigger circuit can force the first MOSFET tube Q1 turns on. The invention is used for high temperature protection for the electric control switch of the hot swap circuit when it is powered on.

Description

technical field [0001] The invention relates to the field of servers, in particular to a power switch protection circuit and a protection method. Background technique [0002] Hot swapping (Hot swapping or Hot plugging) is "hot plugging", which means that hardware can be plugged or unplugged while the computer is running. With appropriate software, peripheral devices that support hot-swap can be inserted or removed without turning off the power, without causing the host or peripherals to burn, and new devices can be detected and used in real time. [0003] In the server world, hot-plug is conventionally implemented by connecting an electronically controlled switch and a current-sense resistor in series between the supply and the load. The electronically controlled switch generally adopts triode, and usually adopts MOS tube (ie, MOSFET tube) to ensure that the back-end load will not be damaged due to abnormal phenomena (such as voltage dip, inrush current, etc.) connected to...

AI Technical Summary

Problems solved by technology

However, when the system is powered off and restarted after a period of time, it is very likely that the temperature of the MOS tube itself and the temperature of the surrounding environment are already high but the MOS tube is forcibly turned on, which is very likely to cause the MOS tube to fail. The phenomenon of burning due to high temperature opening

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