H11B255M-V

Optoisolators - Transistor, Photovoltaic Output

The H11B255M-V device is an optoisolator, specifically a transistor, photovoltaic output type. It consists of a source of infrared emission (LED) in close proximity to a phototransistor. The device is designed to electrically isolate, or link, two different circuits by use of light rather than a direct electrical connection. The H11B255M-V utilizes a minimal power input signal to drive a controlled output. It is an effective means of protecting sensitive electronic equipment from possible voltage or other power surges that might be applied by another circuit.

Features & Benefits

• High speed switching of 1.5 µs maximum
• DC input current of 1 mA
• High input impedance of greater than 10 MΩ
• High dielectric strength between input and output of up to ±1000 V
• Total device package size of less than 5.0 mm
• High frequency response of up to 170 kHz from collector to emitter

Working Principle

At the heart of the H11B255M-V is a light emitting diode (LED) and a phototransistor. The LED emits infrared light, either at a constant level or when a pulse signal is applied to the power input. The LED light is received by the phototransistor, which is then triggered and an output signal is produced. The device is designed to ensure that no electrical current travels between the input and output circuits, providing a degree of electrical isolation that provides added protection for sensitive electronic components.

The device is designed to isolate two circuits by means of an optically-coupled signal. The light emitting diode provides a light source, which is received by the phototransistor. The phototransistor then uses the light source to generate a current, and the output is produced. This results in a low input current that is used to control a higher output current.

The device has many applications, including but not limited to: isolation of touch screens, contact-less switch operations, protection from electrical surges, smart card read/write interface and control of contact-less motors. It has also found uses in the medical field, such as optical isolation between patient monitoring equipment and external medical devices. In addition, the device is well-suited for process control in hazardous and contaminated environments, providing protection to delicate circuitry from spikes, static discharges, and other power-related issues.

Conclusion

The H11B255M-V device is an optoisolator, designed to provide a signal input from one circuit to another whilst resisting electrical noise. It utilises the power of infrared light to transmit a signal, which is then detected by a phototransistor to produce a resulting output. It is a highly versatile device, which has many applications both in industry and beyond. Its high switching speed, high input impedance, total device package size and high frequency response make it an attractive option for users who require robust optical-isolation performance.