Specifications: The APY277G1EH is a compact, high-voltage SMD-4 PhotoMOS SSR. It is a 1 Form A (SPST-NO) device capable of handling 700mA at up to 200V AC/DC. It features a low 0.5Ω on-state resistance, 5000Vrms isolation, and switching times of 800μs (turn-on) and 50μs (turn-off). It is designed for wide temperature operation (-40°C to 85°C) and is controlled by 1.2-1.5VDC. Application Scenarios: Suited for applications requiring a balance of moderate current, higher voltage, and compact size. Typical uses include industrial control of 3-phase system monitoring relays, HVAC compressor and fan controls, appliance motor control (e.g., in air conditioners, refrigerators), power management in renewable energy systems, and as a reliable switch in professional audio/video equipment.