High idle power revisited


Author Message
poida

Guru

Joined: 02/02/2017
Location: Australia
Posts: 1400
Posted: 10:06am 06 Sep 2023      

I see a rather large difference in
turn on (& off) delay and rise times between the IRFP4468 and the HY4008

The test conditions for the parts are different so it's apples and oranges
but it surely must give some guidance...

IRFP4468: tested at Vgs = 10V, Rg = 2.7 Ohms

turn on delay: 52ns
rise time: 230ns
turn off delay: 160ns
fall time: 260ns

HY4008: tested at Vgs = 10V, Rg = 6 Ohms

turn on delay: 28ns
rise time: 18ns
turn off delay: 42ns
fall time: 54ns

clearly the HY4008 will switch a lot faster than the IRFP4468

total Gate charge is 195nC for the HY4008
and 360nC up to 580nC for the IRFP4468

I think the slower switching IRFP4468 require a longer deadtime than what you have designed. The shoot through is causing the high idle power consumption.
Edited 2023-09-06 20:08 by poida