What is PIN Diode:
PIN Diode is the type of diode. The pin diode consists of heavily doped p and n regions separated by an intrinsic region. When reverse biased , the pin diode acts like a nearly constant capacitance. When forward biased, the pin diode acts like a current controlled variable resistance. The low forward resistance of the intrinsic region decreases with increasing current.
Applications of PIN Diode
Pin diodes are used as a dc controlled microwave switch operated by rapid changes in bias or as a modulating device that takes advantage of the variable forward resistance characteristic. Since no rectification occurs at the pn junction, a high frequency signal can be modulated by a lower frequency bis variation. A pin diode can also be used in attenuator applications because its resistance can be controlled by the account of current.