CIRCUIT AND METHOD FOR DRIVING SYNCHRONOUS RECTIFIER

PURPOSE: Synchronous rectifier driving circuit and a driving method are provided to offer a stabilized switch driving signal by making a main switch and a synchronous rectifier not being turned on simultaneously. CONSTITUTION: A main switch on-driving detection unit (10) detects a signal of a secondary side of a transformer according to on-operation of a main switch of a direct current (DC) - direct current (DC) converter. A signal inversion and triangular wave generation unit (20) forms a waveform signal inversed with a voltage signal waveform across a synchronous rectifier. A comparison reference signal generation unit (30) receives a signal from the signal inversion and triangular wave generation unit and generates a DC waveform reference level signal for controlling driving time. A synchronous driving signal generation unit (40) compares the reference level signal and a triangular wave and applies an on-off driving signal to the synchronous rectifier. An on-driving overlap prevention unit (50) removes overlapping with an on-driving range of the main switch from an on-driving control signal of the synchronous rectifier. [Reference numerals] (10) Main switch on-driving detection unit; (20) Signal inversion and triangular wave generation unit; (30) Comparison reference signal generation unit; (40) Synchronous driving signal generation unit; (50) On-driving overlap prevention unit