4N35FVM

4N35FVM Application Field and Working Principle

The 4N35FVM is a light-activated isolation device manufactured by On Semiconductor. It belongs to the optoisolators family, specifically processing Transistor, Photovoltaic Output applications. It was designed around the concept of creating an optically-coupled integrated circuit that would protect and isolate microcomputer components from external environmental factors. Through physical and electrical isolation, it ensures the safe operation of the system without interfering with the primary power sources. The 4N35FVM is particularly suitable for use in hybrid cars, navigation systems, GPS, and security applications due to its high speed switching capability and low power consumption.

The 4N35FVM consists of a main component, the LED or light-emitting diode, and a phototransistor. The LED converts electrical energy into visible light which is then absorbed by the phototransistor, activating the switch or connection. The entire operation of the device is based on the principle of photoconduction, where the LED is used as the emitting element and the phototransistor as the receiving element. The phototransistor behaves like an amplifier, transferring the signal power from the LED to the output.

In operation, the LED is supplied with a forward-bias voltage at just the right current, typically 10 mA. When the LED emits light, photons are absorbed by the phototransistor and allowed to pass through its gain factor, increasing the amount of current that can flow to the output. Conversely, when the LED is no longer emitting light, the phototransistor is not activated, and the output is turned off.

The 4N35FVM is designed for triggering on-and-off switches like relays or thyristors. As the LED-phototransistor combination operates in low wattage, it is essential to use the correct voltage and current in order to maximize efficiency. Also important is selecting the right LED intensity, which should be equal to or higher than the phototransistor\'s performance, as this will ensure the device is able to switch even in bright light.

In conclusion, the 4N35FVM is a versatile optoisolator for use in digital and analog applications. It comes with a wide range of specifications, from high-speed switching and low power consumption to temperature and humidity resistance. Furthermore, it is cost-effective and easy to install due to its small size and lightweight design. Combining principles of photoconduction, LED-phototransistor interconnection, and low wattage operation, it is ideal for all types of optoelectronic systems.