Characterization of paralleled super junction MOSFET devices under hardand soft-switching conditions

The super junction (SJ) MOSFET exhibits conduction and switching properties similar to those of conventional power MOSFETs. In this paper, we investigate possible benefits and problems associated with connecting SJ MOSFET in parallel for high-power applications. Measured circuit performances of paralleled SJ MOSFET devices are evaluated under hard- and soft-switching conditions. The measurements include (1) turn-on and turn-off switching voltage and current comparison, (2) gate driver resistance effects on current sharing between paralleled SJ MOSFET devices, and (3) SJ MOSFET body diode behavior under hard- and soft-switching conditions. Two test circuits are developed for paralleled SJ MOSFET evaluation. One is an auxiliary resonant snubber chopper for the near zero-voltage switching test, and the other one is an auxiliary resonant snubber inverter for the true zero-voltage condition test. Experimental results indicate that SJ MOSFET can be paralleled without the need for precise device matching if the gate drive resistances are closely matched.