STD5N50 STD5N52K3 STD5N52K3 5N52K3 STD5N52K3 MOSFET或IGBT STD5N52K3 MOSFET或IGBT开关IC STD5N52U STD5N52U D5N52U STD5N52U MOS(场效应管) STD5N52U 其他IC STD5N52U-VB