PhotoMOS relays for automotive and industrial applications
PhotoMOS relays with a MOSFET output enjoy an almost unlimited lifetime if used according to the specifications. Moreover, they are extremely reliable, unaffected by vibration, and their On-resistance remains stable throughout their entire lifetime. In addition to our broad product line-up for the industrial market, automotive-qualified types are also available.
The basic construction of the PhotoMOS relay can be seen in the illustration. Light emitted from an LED on the input side passes through an isolator that is permeable to light and is detected by a solar cell. Via a trigger circuit, the solar cell‘s output voltage controls the gates of two source-coupled MOSFETs at the output. This arrangement allows PhotoMOS relays to switch both AC and DC loads. The integration of MOSFET technology in PhotoMOS relays significantly differentiates them from semiconductor relays with triacs or transistors at the output.