An avalanche photodiode (APD) is a highly sensitive electronic semiconductor device that utilizes the photoelectric effect to convert light into electricity.
High sensitivity and low noise, Fast reaction and Low-light level measurement. Avalanche photodiodes are silicon photodiodes with an internal amplification mechanism. As with a conventional photodiode, electron-hole pairs are produced by absorbing incident photons. A high reverse voltage creates a strong internal electric field that accelerates the electrons through the silicon crystal lattice and generates secondary electrons by impact ionization. The resulting electron avalanche can produce gains of up to several hundred.
An avalanche diode is a type of semiconductor device that has been specifically designed to operate in the reverse breakdown range. These diodes are used as pressure relief valves that control the system pressure to protect electrical systems from overvoltages. The symbol of this diode corresponds to the Zener diode. The avalanche diode consists of two terminals, namely anode and cathode.