INSULATION SYNCHRONOUS RECTIFICATION TYPE DC/DC CONVERTER, SYNCHRONOUS RECTIFICATION CONTROLLER, POWER SUPPLY EMPLOYING THE SAME, POWER SUPPLY ADAPTER, ELECTRONIC APPARATUS, AND CONTROL METHOD FOR SYNCHRONOUS RECTIFICATION CONTROLLER

摘要

PROBLEM TO BE SOLVED: To solve a problem that may occur in a continuous mode.SOLUTION: A pulse generator 304 turns a pulse signal S1 to an ON level that instructs ON of a synchronous rectification transistor M2 when turn-off of a primary-side switching transistor M1 of a DC/DC converter 200 is detected, and turns the pulse signal S1 to an OFF level that instructs OFF of the synchronous rectification transistor M2, when it is detected that a current of a secondary winding wire W2 of a transformer substantially becomes zero. A forcible off circuit 330 forcibly turns off the synchronous rectification transistor M2 after the lapse of a predetermined time-up period from the detection of turn-on of the switching transistor M1.SELECTED DRAWING: Figure 3