Multi-channel output DC-DC inverter

Abstract

This invention discloses a multi-channel output DC-DC converter including a transformer, a primary an a sub-commutation circuits, a PWM control circuit, in which, a secondary winding output of the transformer is connected with the inputs of the primary and the sub-commutation circuits, a chopper is composed of a first and a second switch tubes in series, the PWM control circuit outputs pulses with the duty ratio of D and 1-D to the control end of the two switch tubes to fix up the dead time of them, a resonance loop is composed of a resonance capacitor, a first and a second resonance inductors parallel to the first winding of the transformer, the input of the loop is connected with the chopper, the first inductor resonates with the capacitor to shut up the quasi-zero current of the two tubes and the second, the first inductor resonate with the capacitor to turn on the zero voltage of the two switch tubes.

Description

technical field [0001] The invention relates to a DC-DC converter, in particular to a multi-channel output DC-DC converter. Background technique [0002] In modern electronic equipment, multiple DC voltage sources of different levels are usually required for power supply. If a single output power supply is used for each level of DC voltage, although the power supply requirements of the load can be well met, the cost, volume and weight of the power supply will increase. Therefore, a multi-output DC-DC converter is generally used to provide multiple DC voltage sources of different levels. [0003] like figure 1 As shown, among the existing multi-output DC-DC converters, the dual-tube forward multi-output DC-DC converter is widely used. But this topology circuit is difficult to realize soft switching. Since there is no soft switch, the switching loss of the switching tube is large, and the rectifier tube needs to use a diode with a higher withstand voltage and a larger on-s...

AI Technical Summary

Problems solved by technology

But this topology circuit is difficult to achieve soft switching

Since there is no soft switch, the switching loss of the switching tube is large, and the rectifier tube needs to use a diode with a higher withstand voltage and a larger on-state voltage drop, and the rectification loss is large, so the efficiency of this topology circuit is low.

In addition, because there is no soft switching, the di / dt of the switch tube is poor, the reverse recovery current of the diode is large, and the electromagnetic compatibility (EMC) is poor

In addition, the dual-transistor forward multi-output converter uses output inductors, and the cost is relatively high

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