Predictive Gate Drive Boosts Converter Efficiency

Predictive Gate Drive™ is a novel digital control-driven technique that optimizes MOSFET turn-on and turn-off delays in synchronous rectifiers. It uses a closed loop feedback system to detect body-diode conduction, and continuously adjusts dead-time delays to minimize the conduction time interval. Depending upon operating frequency and output voltage, the Predictive Gate Drive™ control method can improve overall converter efficiency by two to four percent and the synchronous rectifier MOSFET power dissipation by 20 to 40 percent over currently available drive techniques. This paper compares this innovative new control technique to previous and currently existing related technologies. The problem of body-diode conduction is discussed and used to demonstrate efficiency improvements when the Predictive Gate Drive™ technology is applied.