This application note introduces Fairchild Semiconductor's FCS fast body diode MOSFET (AN-7536), which can be used in phase-shifted ZVS PWM full-bridge DC/DC converters. The FCS MOSFET has fast reverse recovery characteristics, which can achieve ZVS switching conditions in phase-shifted bridges, thereby improving efficiency and power density.
The document introduces the Fairchild FCS Fast Body Diode MOSFET (FRFET) as a solution for the Phase-Shifted ZVS PWM Full Bridge DC/DC Converter topology. It addresses the issue where conventional MOSFET body diodes can cause device failure due to reverse recovery characteristics, particularly at light loads where the converter loses Zero Voltage Switching (ZVS) conditions. The FRFET is designed to overcome these potential diode reverse recovery problems.
The main applications include telecom power supply, main frame computer and server, welding, and steel cutting.
It is used to overcome the potential diode reverse recovery problem caused by conventional power MOSFET body diodes, which can lead to device failure during switching.