A kind of synchronous rectification converter and its switch tube driving method

Abstract

The present invention provides a synchronous rectification converter and a switching tube driving method thereof, comprising a PWM control circuit, a switching tube driving circuit, a first switching tube and a second switching tube; the switching tube driving circuit outputs a control signal according to a control signal terminal and The enable signal output by the enable signal terminal controls the switching states of the first switch tube and the second switch tube; the switch tube drive circuit includes a first Schmitt trigger and a second Schmitt trigger; when the first switch tube is closed During the process, the first Schmitt trigger controls the second switching tube to turn on according to the gate voltage of the first switching tube; during the closing process of the second switching tube, the second Schmitt trigger controls The gate voltage controls the first switching tube to be turned on, so that a long delay time is not required to prevent the first switching tube and the second switching tube from being turned on at the same time, thereby improving the conversion efficiency of the synchronous rectification converter.

Description

technical field [0001] The present invention relates to the technical field of synchronous rectification converters, and more specifically relates to a synchronous rectification converter and a method for driving a switch tube thereof. Background technique [0002] A DC / DC converter, also known as a DC / DC converter, is a voltage converter that converts an input voltage into an effective output fixed voltage. DC / DC converters are generally divided into three categories: step-up DC / DC converters, step-down DC / DC converters, and step-down DC / DC converters. [0003] An existing non-synchronous rectification step-down DC / DC converter such as figure 1 As shown, it includes a PWM control circuit, a switch tube M1, a diode D1, an inductor L, a capacitor C and a load RL. When the PWM control circuit controls the switch tube M1 to turn on, the input voltage Vg supplies power to the load RL through the inductor L, and also charges the capacitor C at the same time. During this proces...

AI Technical Summary

Problems solved by technology

[0007] In view of this, the present invention provides a synchronous rectification converter and its switching tube driving method to solve the problem of low conversion efficiency of the synchronous rectification converter caused by too long delay time of the inverter chain

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