onsemi FOD817B3SD 4-Pin DIP Phototransistor Optocoupler: Features, Specifications, and Applications

The onsemi FOD817B3SD is a widely used 4-pin DIP (Dual In-line Package) phototransistor optocoupler designed to provide excellent electrical isolation between high-voltage and low-voltage circuits. This component is essential in applications where noise suppression, voltage level shifting, and safety isolation are critical. By utilizing an infrared LED optically coupled to a silicon phototransistor, it ensures signal transmission without direct electrical connection.

Key Features

One of the standout features of the FOD817B3SD is its high isolation voltage of 5000 Vrms, making it suitable for high-reliability applications. It offers a minimum current transfer ratio (CTR) of 50% at an input current of 5 mA, ensuring efficient signal coupling. The device operates over a broad temperature range from -55°C to +110°C, providing stability in harsh environments. Additionally, its compact DIP package allows for easy PCB mounting and is compatible with standard automated assembly processes.

Specifications

- Input Forward Current (IF): 60 mA maximum

- Collector-Emitter Voltage (VCEO): 80 V

- Power Dissipation: 250 mW

- Rise and Fall Time: 4 μs (typical)

- Isolation Resistance: 10^12 Ω at 500 V

- Compliance with international safety standards such as UL and CSA.

Applications

The FOD817B3SD is versatile and finds use in numerous fields. It is commonly employed in switch-mode power supplies (SMPS) for feedback control and regulation. In industrial systems, it serves as an isolation component in PLCs, I/O modules, and motor controls. It also protects microcontrollers and logic circuits in consumer electronics from voltage spikes and noise. Furthermore, it is used in telecommunications equipment and medical devices where safety and reliability are paramount.

ICGOOODFIND

The onsemi FOD817B3SD optocoupler stands out for its robust isolation performance, thermal stability, and cost-effectiveness, making it a preferred choice for designers seeking reliability in diverse electronic systems.

Keywords: Optocoupler, Electrical Isolation, Current Transfer Ratio, Phototransistor, Switch-Mode Power Supplies