 | This article includes a list of references, related reading, or external links, but its sources remain unclear because it lacks inline citations. (July 2022) |
 Layers of a PIN diode | |
| Type | Semiconductor |
|---|---|
| Invented | 1950 |
| Electronic symbol | |
 The diode may be denoted by "PIN" letters on the diagram | |
A PIN diode is a diode with a wide, undoped intrinsic semiconductor region between a p-type semiconductor and an n-type semiconductor region. The p-type and n-type regions are typically heavily doped because they are used for ohmic contacts.
The wide intrinsic region is in contrast to an ordinary p–n diode. The wide intrinsic region makes the PIN diode an inferior rectifier (one typical function of a diode), but it makes it suitable for attenuators, fast switches, photodetectors, and high-voltage power electronics applications.
The PIN photodiode was invented by Jun-Ichi Nishizawa and his colleagues in 1950. It is a semiconductor device.