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MYTH #2: e-mode devices have no Qrr

MYTH #2: e-mode devices have no Qrr

Posted Date: 2023-10-14

Actuality: When switching from reverse conduction to off-state, the reverse restoration cost accounts for not solely bipolar transport minority carriers recombination but additionally the formation of the space-charge area, which is successfully equal to the output cost (Qoss). It’s true that GaN HEMTs don't have any reverse conduction bipolar transport, however they however do have output capacitance that must be charged throughout reverse restoration. In a nutshell, Qrr = Qoss. Qrr can't be zero. Fantasy busted!

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