DC-DC CONVERTER CIRCUIT

摘要

A DC-DC converter circuit comprises a switching circuit for switching a DC power supply with a primary switch element, a transformer having primary winding to which the output from the switching circuit is applied and secondary winding for outputting a voltage transformed at a predetermined transformation ratio, and a secondary diode for rectification connected with the secondary winding of the transformer. The circuit further comprises a regenerative snubber circuit, which is connected between the rectification outputs of the secondary diode and includes a series circuit of a discharge prevention diode and a snubber capacitor and a switch element for regeneration connected in parallel with the discharge prevention diode, and a control section for turning on the switch element for regeneration for a predetermined time from the off timing of the primary switching element. The predetermined time is set to a time for substantially discharging the snubber capacitor due to a reverse recovery time when the secondary diode is turned off.