Elimination of Secondary MOSFET Avalanche Failure in DC Bus Converters

摘要：

A detailed avalanche mechanism on secondary synchronous rectification MOSFETs is described in half bridge DC bus converters. A positive feedback loop is identified that causes a high dv/dt before the avalanche. High dv/dt and high current can cause secondary power MOSFET failure due to avalanche under certain operation condition. Two simple circuit implementations were used to demonstrate how to reduce the dv/dt by eliminating the positive feedback loop. The reduced dv/dt protects the secondary power MOSFETs from a potential avalanche failure. Demonstrated methodology can be applied to any converter exposed to a similar failure mechanism to improve converter reliability. The high dv/dt and high current condition can also be used to test power MOSFET avalanche capabilities.

作者: Weidong Fan

作者单位: International Rectifier 220 Kansas St.El Segundo, CA 90245

会议类型: 国际会议

会议名称: PCIM China 2007(International Conference Power Electronics)(2007年中国电力电子技术国际会议)

会议地点: 上海

会议语种:英文

在线出版日期: 2007-03-21（万方平台首次上网日期，不代表论文的发表时间）