Specifications： The APY217EH is a compact, high-isolation PhotoMOS solid-state relay in an SMD-4 package. This SPST-NO device switches loads up to 200V AC/DC at 200mA, with a 5Ω on-state resistance. Its key feature is 5000Vrms isolation, ensuring robust safety between control and load circuits. It offers fast 400μs/50μs switching, operates from -40°C to 85°C, and is controlled by 1.2-1.4VDC logic signals. Packaged in Tape & Reel, it is ideal for automated SMT assembly. Application Scenarios： This relay is designed for applications requiring reliable isolation, low-power switching, and high-density layouts. Its high isolation makes it suitable for medical devices (patient monitors, diagnostics) and industrial automation (PLC I/O, sensor interfaces), where it provides noise immunity and protects control logic. The compact SMD-4 form factor and speed also suit telecommunications (router/switch port control, signal routing) and test equipment (channel multiplexing). It serves as a long-life, silent alternative to electromechanical relays in consumer appliances, automotive electronics, and other space-constrained, harsh environments.