CNY17-3S

Optoisolators - Transistor, Photovoltaic Output

The CNY17-3S optocoupler (optoisolator) is a 6-pin dip phototransistor optoisolator. It provides a high degree of electrical isolation between the input and output stages for operations in noisy environments. It contains an infrared emitting diode (IRED), a high gain phototransistor and an opaque black plastic case. It is widely used in different areas, ranging from the railway industry to the household appliance industry. In this article, the application field and working principle of the CNY17-3S are discussed.

Application Field

The CNY17-3S optoisolator is mainly used in switching applications. It is suitable for the isolation of signals, especially in noisy environments. The device is compatible with TTL and CMOS and can be used as a gate driver for high-power logic devices. It is also used for power transistor and low power Darlington applications.

The CNY17-3S is also used in measurement equipment, such as digital pressure gauges, bar code readers and flow controllers. It is also used as a current switch form inductive load and provides voltage isolation. Additionally, the device is also used in current transformer applications to provide current isolation.

Working Principle

The CNY17-3S optoisolator consists of an infrared emitting diode (IRED) and a high-gain phototransistor housed in an opaque black plastic case. The IRED is used to produce light when a forward voltage (Vf) is applied to its terminals. The light is then directed to the collector-base junction of the phototransistor, where it is converted into electrical current. When sufficient light is detected at the collector-base junction of the phototransistor, the transistor will switch on and cause the collector current to increase. This collector current will then flow through the phototransistor output terminals and can be used to drive the load.

In addition to its primary function of providing electrical isolation between the input and output stages, the CNY17-3S optoisolator also provides a degree of noise reduction. As the light produced by the IRED is relatively inadequate, it is filtered out efficiently by the surrounding insulators, thereby reducing the effect of electrical noise on the output signal.

Conclusion

The CNY17-3S optoisolator is a versatile device that can be used in a wide variety of applications. It provides electrical isolation between input and output stages, as well as some degree of noise reduction. Due to its low price and simple construction, it is becoming increasingly popular in industrial and commercial applications.