AQY280SX is a single-channel PhotoMOS relay designed for general-purpose switching applications requiring high voltage isolation and low leakage current. It features a maximum load voltage of 350V peak AC/DC with a continuous load current rating of 120mA, making it suitable for high-voltage control circuits. The relay exhibits low on-resistance of 2.5O maximum and extremely low off-state leakage current of 1µA, with an I/O isolation voltage of 1,500V AC and I/O isolation resistance of 1,000MO minimum. Operating over a temperature range of -40°C to +85°C, the device provides fast switching with typical turn-on time of 0.3ms and turn-off time of 0.5ms. Common applications include modems, telephone equipment, security systems, and sensor interfaces where reliable high-voltage switching with minimal leakage is essential.