Photodiode Characteristics

Info/ characteristic

Photodiode

Photodiode is an electronic device that can convert light into a voltage or current signal. This happen which the photons are absorbed into the photodiode and it generates current. Although photodiode generate current when photons is absorbed, but there is also a small amount of current produced when no light is present. The magnitude of the photocurrent is depending on the wavelength of the incident light. Photodiodes have slow response time as the surface area of the optical filter or built-in lenses increases. Photodiodes are usually use PIN junction rather than p-n junction because this will increase the response speed. So this also means that P-n junction photodiode is used in low sensitivity and low frequency devices, while for the high sensitivity and high frequency devices is by using the PIN junction. There are two more different type of photodiode other than p-n junction and PIN, which are Avalanche photodiode and Schottky photodiode. Avalanche photodiode usually in areas of low light while Schottky photodiode is based on the technology of Schottky diode

It is an effect where the voltage or electric current is created in the material due to exposure to light. It is different from the photoconductive mode. When some light source is shine or enter on the surface of the photodiode, the electron in valence band absorb the light energy or heat energy and turn into excited state, then jump to the conduction band and become free electron. These free electrons will then diffuse or accelerated to other materials and this generates electromotive force or current. This is how light energy is converted to heat energy. The example application that uses this operation principle is solar cell. Therefore, by constructing a solar cell, a large number of individual photodiode are needed, so there will have a larger active area for this process and gain more