What is fast recovery diode?

  • Fast recovery diodes have the reverse recovery time of the order of 25-100nS.
  • Fast recovery diode consists of a highly doped P type and n+ type layers sandwiched by a lightly doped n– layer.
  • The thickness of n– layer is increased to increase the voltage blocking capacity.
  • The reverse recovery time is reduced by reducing the stored charge in the neutral and minimizing carrier life time. This is achieved by forming recombination centers in neutral region.
  • For very high frequency applications, PIN diodes are used.
  • Fast recovery diodes have ratings from 1A/50V to 1kA/3kV with reverse recovery time less than 5μS.