The 4N26M is a general-purpose optocoupler designed for applications requiring electrical isolation between signal circuits. It features a minimum current transfer ratio (CTR) of 20% with an input forward current of 10 mA and a collector-emitter voltage of 10 V. The device provides a high isolation voltage of 4,170 VACRMS for one minute and supports a collector-to-emitter voltage up to 30 V. Common applications for the 4N26M include power supply regulators, digital logic inputs, and microprocessor inputs, where it provides reliable signal coupling while maintaining electrical isolation.