关键词: 光继电器, 光电二极管阵列, 功率MOS管, 开关特性

Abstract: In recent years，photoelectric MOS relays are arousing increasingly interest for it’s high quality of reliability and switching speed. The photoelectric relays are a new kind of Solid-State-Relay by optical signal couple technology. It combined optical devices and power semiconductor devices packaged in one shell. The thesis discuss the theory and structure of the photoelectric MOS relays, by simulating the character of the photo diode array inside the relay，confirm the photo-diode substrate density and absorption thickness. By choose the appropriate power-MOS, the photoelectric relays can meet the need of the market.

Key words: photoelectric relays, photo-diode array, power MOS, switching characteristic