Dynamics of reverse recovery of high-power P-i-N diodes

The reverse recovery of high-power P-i-N diodes is studied under resistive (step recovery) and inductive (ramp recovery) switching conditions. It is shown that, under resistive switching, the reverse recovery characteristics of P-i-N diodes depend significantly on whether it is turned off during the turn-on transients (forward recovery) or whether it is turned off when the diode has reached a steady forward conducting state. It is pointed out that, under inductive switching, the voltage across the diode becomes negative even when the current in the diode is still, ramping down in the reverse direction. It is also shown that the ramp recovery characteristics of P-i-N diodes depend quite significantly on the circuit operating conditions and the reverse recovery characteristics can be different even if the current that the diode turns-off and the rate at which the diode current ramps down are the same. Finally, a novel test circuit is proposed and employed to carry out accurate reverse recovery measurements of high-power P-i-N diodes under resistive switching.