Diodes What is diode In electronics a

Diodes

What is diode In electronics, a diode is a two-terminal electronic component with asymmetric conductance, it has low resistance to current flow in one direction, and high resistance in the other. A semiconductor diode, the most common type today, is a crystalline piece of semiconductor material with a p–n junction connected to two electrical terminals.

LED A light-emitting diode (LED) is a semiconductor light source. LEDs are used as indicator lamps in many devices and are increasingly used for general lighting. Appearing as practical electronic components in 1962, early LEDs emitted low-intensity red light, but modern versions are available across the visible, ultraviolet, and infrared wavelengths, with very high brightness.

Diode logic (DL) or dioderesistor logic constructs Boolean logic gates from diodes acting as electrically operated switches. Not all logical functions can be implemented in diode logic alone; only the noninverting logical AND and logical OR functions can be realized by diode gates. If several diode logic gates are cascaded, the voltage levels at each stage are significantly changed, so one-stage applications are used.

Transistor diode model In a diode model two dio des are backto-back connected to make a PNP or NPN bipolar junction transistor (BJT) equivalent.

NPN and PNP transistors To make an NPN transistor, the anodes of both diodes are back-toback connected to form a large P type base region. To make a PNP transistor, the cathodes of both diodes are back-to-back connected to form a large N type base region.