Diode

From Electronics Wiki

You can think of a diode as a one-way valve for electrons to flow. It allows current only in one direction. Another commonly-used term for a diode is a rectifier. They may be used to change alternating current to direct current.

The following example shows the operation of a typical diode in a circuit. Notice that there can be a small amount of reverse flow before the diode cuts off, due to capacitance. Notice also that there is a voltage drop from input to output.

types of diodes

• LED light emitting diode, are available in many different colours; forward voltage drop depends on wavelength, usually from 1.5 to 5 volts
• Shottky diodes generally have higher power and lower forward voltage drop than other types
• silicon
• germanium
• zener diodes are used in voltage control; non-catastophic reverse-breakdown