The IL217AT is a transistor output optocoupler manufactured by Vishay. It features a single phototransistor output and has a current transfer ratio (CTR) of over 100%, making it suitable for use in applications that require a high level of isolation. The device is suitable for use in power supply isolation, AC and DC line interface, signal interface, speed sensing, and more. The package options for the part includes DIP-8, SMD-8, and SMD-4, and complies with the requirements of safety standards IEC/EN/UL 60950-1.