Views: 20 Author: Site Editor Publish Time: 2020-07-06 Origin: Site
There are many different forms of diode and for most types there is a distinct circuit symbol.
Some of the major types of diode include the PN junction, Schottky, varactor, Zener or avalanche reference diode, photo diode, light emitting diode. For all of these there are distinct circuit symbols. Each of these diode circuit symbols incorporates the basic diode format, but is modified to indicate the different function.
Table: Diode Circuit Symbols
Symbol | Name | Description |
 | Diode | Allows current flow in one direction only (left to right). |
 | Zener Diode | Allows current flow in one direction, but also can flow in the reverse direction when above breakdown voltage |
 | Schottky Diode | A diode with low voltage drop |
 | Varactor / Varicap Diode | Variable capacitance diode |
 | Tunnel Diode | A heavily doped p-n junction diode in which the electric current decreases as the voltage increases. |
 | Light Emitting Diode (LED) | LED emits light when current flows through |
 | Photodiode | Photodiode allows current flow when exposed to light |
