Dual-drive power supply slow start circuit

Abstract

The invention relates to a dual-drive power supply slow start circuit, which comprises a power switch tube, a first-stage drive circuit and a second-stage drive circuit. The source electrode of the power switch tube is connected with an input power supply, and the drain electrode is connected with an output power supply; the input end of the first-stage driving circuit is connected with an input power supply, and the output end of the first-stage driving circuit is connected between the source electrode and the grid electrode of the power switch tube; the input end of the second-stage driving circuit is connected with the output power supply, the output end of the second-stage driving circuit is connected between the drain electrode and the grid electrode of the power switch tube, and the second-stage driving circuit is used for starting to work after the power switch tube is driven to be conducted, driving self-locking is achieved, and normal output of the output power supply is guaranteed; and meanwhile, when the input power supply drops to an undervoltage working point, the first-stage driving circuit and the second-stage driving circuit simultaneously control the power switch tube to be disconnected. According to the dual-drive power supply slow start circuit provided by the invention, self-excitation drive power supply can be realized, an under-voltage protection function is realized, and the drive reliability is better; and false triggering output when the input power supply oscillates can be prevented, and the safety performance is better.

Description

technical field [0001] The present application relates to the technical field of power supply application, in particular to a dual-drive power supply slow-start circuit. Background technique [0002] With the continuous development of communication technology, communication equipment has higher and higher requirements for power supply, which makes power protection technology more widely used in power supply applications. Usually, power supply slow start circuits are used for power protection. [0003] Existing power supply slow-start circuits all adopt a single-drive control mode, and an auxiliary drive power supply and a driver chip are required to realize the slow-start function. However, in the existing single-drive control mode, the PMOS power switch is easily damaged when the input power is oscillated at startup, and the circuit malfunctions when the drive circuit fails. [0004] Based on this, how to solve the problems of easy false triggering and power failure in rel...

AI Technical Summary

Problems solved by technology

However, in the existing single-drive control mode, the PMOS power switch is easily damaged when the input power is oscillated at startup, and the circuit fails when the drive circuit fails.

[0004] Based on this, how to solve the situation of easy false triggering and power failure in related technologies, and improve the reliability of the power supply slow start circuit is the core of our research and development

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