Optocoupler PC817

PC817 1‑Channel Optocoupler: Precision Isolation for Digital Signals

The PC817 is a compact, 1‑channel optocoupler that delivers reliable electrical isolation between the input and output sides. By using an infrared LED as the input source and a dual‑phototransistor output, it provides galvanic isolation while maintaining fast switching speeds suitable for digital logic, microcontroller interfacing, and sensor signal conditioning. Its high common‑mode voltage handling and consistent CTR performance make it ideal for protecting sensitive electronics from high‑voltage spikes and noise.

Designed in a durable TO‑92 package, the PC817 supports operation up to 5 kV isolation, a CTR of 50 %–100 % at 5 mA input, and rise/fall times of 300 ns, enabling robust edge‑rate performance. The device’s low forward voltage drop and minimal output leakage reduce power consumption, while its narrow coupling angle enhances signal fidelity. These attributes provide a cost‑effective, low‑profile solution for interface circuits, industrial automation, and power control applications.

• Key Spec 1: CTR 50 %–100 % (5 mA input)
• Key Spec 2: Isolation Voltage 5 kV (ripple)
• Key Spec 3: Rise/Fall Time 300 ns (typ.)
• Common Use Case: Programmatic isolation between microcontroller logic and high‑voltage or high‑noise hardware stages