Specifications: The APV221E is a through-hole DIP-6 packaged PhotoMOS solid-state relay with a 1 Form A (SPST-NO) contact. It handles 200mA load current at up to 60V AC/DC. It has a 3Ω on-state resistance, provides 5000Vrms of isolation, and features symmetrical, fast 50μs switching for both turn-on and turn-off. Its operating temperature spans -40°C to 85°C, and it is controlled by a 1.2-1.4VDC input signal. Application Scenarios: Suited for general-purpose, low-power isolation and switching where through-hole mounting is preferred for prototyping or high-reliability applications. Typical uses include legacy industrial control board upgrades, educational and test bench setups, sensor signal isolation, low-power relay or solenoid coil drivers in security and alarm systems, and as a reliable, long-life replacement for mechanical signal relays in instrumentation, data acquisition systems, and telecom infrastructure.