How to calculate the avalanche energy.

Figure 1 shows the avalanche measurement circuit and Figure 2 shows the avalanche voltage and current waveforms.
Avalanche energy EAS is calculated by using following formula.

          1                   BVDSS
EAS= ー LIAS2  ―――――――
          2                BVDSS -VDD
EAS : Avalanche energy
IAS : Avalanche current
BVDSS : Drain-source avalanche voltage
VDD : Supply voltage
Figure 2 shows reverse recovery current comparison of high speed and standard type of diode

Avalanche ruggedness is the allowable energy in a single pulse.

For MOSFET’s avalanche, please refer to “Maximum Ratings: Power MOSFET Application Notes