An under-voltage protection circuit and power supply thereof

Abstract

The utility model discloses an under -voltage protection circuit and power supply thereof. The under -voltage protection circuit includes voltage detection module and control module, and voltage detection module is used to gather the input voltage of power module and generates voltage sampling signal;The control module is when voltage sampling signal is less than second preset threshold value, and the output control signal makes power module close, and when voltage sampling signal is greater than first preset threshold value, stop output control signal, wherein first preset threshold value is greater than second preset threshold value, and forms under -voltage return difference characteristic. Through above -mentioned mode, the utility model embodiment can produce under -voltage return difference characteristic through double threshold value design, realizes under -voltage protection, effectively prevents the output oscillation when voltage is near the threshold fluctuation, improves system stability, and adopts external circuit to realize accurate under -voltage point setting, and solves the technical problem that under -voltage protection changes greatly with the under -voltage point change of working temperature.

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