A vacuum tube diode has two electrodes, a plate (anode) and a heated cathode. The most common function of a diode is to allow an electric current to pass in one direction (called forward diode direction) while the current is blocked in the opposite direction (reverse direction).
Diodes can be used as rectifiers, signal limiters, voltage regulators, switches, signal modulators, signal mixers, signal demodulators and oscillators. The fundamental property of a diode is its tendency to drive electricity in one direction.
A diode is a device that allows unidirectional current flow only if it operates within a certain voltage level.
A diode only blocks the current in the reverse direction, while the inverse voltage falls within a limited range, otherwise the reverse barrier breaks and the voltage at which this failure occurs is called reverse breakdown voltage. The LED acts as a valve in the electronic and electrical circuit.
A P-N junction is the simplest form of the diode that behaves like an ideal short circuit when it is tilted forward and acts as an ideal open circuit when it is inversely. Besides the simple PN junction diodes, there are different types of diodes, although the basic principles are more or less identical. Thus, a particular diode arrangement can convert alternating current into alternating current, and is therefore sometimes also called a rectifier.
The diode name is derived from the diode, which means a device that has two electrodes.