AN2842 Datasheet, PDF (10/22 Pages) STMicroelectronics – Paralleling of power MOSFETs in PFC topology

Approach to the study
AN2842
Figure 11. Details of current imbalance during turn-off due principally to the voltage
on the gate circuitry
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The switching losses during this instance can became very high and it can cause thermal
runaway with consequent device failure (see Figure 16). Instead, if the two V_THRESHOLD
values are similar, the current profiles assume the same aspect (see Figure 12). During
turn-off operations, the two devices switch in the same way and at the same time, sharing
the current correctly.
Figure 12. Details of current imbalance during turn-off when the voltage on the gate
circuitry is very comparable
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Doc ID 15110 Rev 1
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