STSR30

STSR30 SYNCHRONOUS RECTIFIER SMART DRIVER FOR FLYBACK s s s s s s SUPPLY VOLTAGE RANGE: 4V TO 5.5V TYPICAL PEAK OUTPUT CURRENT: (SOURCE-SINK: 1.5A) OPERATING FREQUENCY: 20 TO 500 KHz INHIBIT BLANKING TIME: 700 ns AUTOMATIC TURN OFF FOR DUTY-CYCLE LESS THAN 14% POSSIBILITY TO OPERATE IN DISCONTINUOUS MODE SO-8 www.DataSheet4U.com DESCRIPTION STSR30 Smart Driver IC provides a high current outputs to properly drive secondary Power Mosfets used as Synchronous Rectifier in low output voltage, high efficiency Flyback Converters. From a synchronizing clock input, withdrawn on the secondary side of the isolation transformer, the IC generates a driving signal with set dead times with respect to the primary side PWM signal. The IC operation prevents secondary side shoot-through conditions at turn-on of the primary BLOCK DIAGRAM switch providing anticipation in turn-off the output. This smart function is implemented by a fast cycle-after-cycle logic control mechanism, based on a high frequency oscillator synchronized by the clock signal. This anticipation is externally set through external component. A special Inhibit function, detecting the voltage across the Synchronous FET, allows to shut-off the drive output during discontinuous mode condition. A Disable pin allows turning off the device during no-load condition reducing overall current consumption. January 2004 1/10 STSR30 ABSOLUTE MAXIMUM RATINGS (Note 1) Symbol VCC OUTGATE DISABLE INHIBIT CK ESD PTOT TSTG TOP Parameter ...