SRM4010

SRM4010 40A Synchronous Rectifier Module C OL OR AD O DIVISIO N DESCRIPTION The SRM4010 Module is a complete solution for implementing very high efficiency Synchronous Rectification and eliminates many of the problems with selfdriven approaches. The module connects to the transformer secondary of a Forward Converter to provide complete high current rectification at output voltages ranging from 5 volts down to 1.0 volt, in a thermally efficient surface mount package. Rectification Efficiency as high as 95% is achieved by avoiding cross conduction. Dedicated Ics provide effective Gate drive of the ultra low Rds(on) MOSFETs used in the module. In conventional self-driven approaches, the MOSFET drive ends as soon as the power transformer finishes resetting. This causes increased losses as the duty cycle decreases. The SRM4010 control circuitry drives either the Forward or the Catch MOSFET over virtually the entire duty cycle. Only a small prediction time, typically 100 ns, is needed to avoid cross conduction. The SRM 4010 is designed to handle large sudden changes in duty cycle. This makes the module suitable for current mode control applications, with large load changes where high bandwidth is needed. Proprietary prediction circuitry eliminates cross conduction for sudden large changes in pulse width. The module is self-powered from the transformer secondary winding and operates over a wide range of peak transformer voltages and PWM frequencies. A 5-Volt Linear Regulator is als...