AQY221R2SZ is a miniature PhotoMOS relay featuring low on-resistance characteristics optimized for AC/DC dual-use switching applications. This R-type variant delivers a typical on-resistance of 0.8O with an output capacitance of 13pF, enabling high-speed switching with turn-on and turn-off times of 0.1ms and 0.06ms respectively. The device is housed in a compact SOP4-pin package with a maximum load voltage of 40V and continuous load current rating of 250mA, operating reliably across a temperature range of -40°C to +85°C. It is particularly well-suited for measuring and testing equipment such as IC testers, liquid crystal driver testers, and semiconductor performance testers, as well as telecommunications, broadcasting, and medical equipment applications where fast, reliable switching with minimal signal distortion is required.