A diode is a two terminal electronic component that conducts current primarily in one direction. It has a low resistance in one direction and a high resistance in the other. The semiconductor diode which is the most type in use today is a crystalline piece of semiconductor material connected to two electrical terminals. The first semiconductor diodes were developed around 1906 but have been developed and refined into the high quality units used today. Most diodes manufactured today are made from silicon but some are made from other materials such as selenium and germanium.
Functions of diodes
Diodes are used to allow electrical current to pass in one direction only while blocking it in the opposite direction it can be viewed as an electrical valve. They can have a more complicated behaviour than this simple action because of their nonlinear current-voltage characteristics. Semiconductor diodes begin conducting electricity only when a certain threshold voltage is present in the forward direction. The voltage drop varies only a little with the current and this effect can be used as a temperature sensor or as a voltage reference. The diodes current-voltage characteristic can be tailored by selecting the semiconductor materials and doping impurities that are introduced into the material during manufacture. This creates specific purpose diodes that can perform many different functions.
Characteristics of diodes
These ingenious little units can be replaced if they malfunction. This can be caused by a large surge of power going through them. They will then fail on purpose to protect a more expensive and sensitive component from receiving the power surge. As diodes are relatively inexpensive they are often placed in front of a highly sensitive and expensive component and are used as a safeguard. The amount of volts or current that a diode can safely transmit is denoted on the diode by means of various colour codes. These ensure that the diode is of the correct range to protect the sensitive component when being replaced. The specifications are also printed on the diode to avoid mistakes. Order an LSA46-2 diode kit from Generator Parts today .