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LTC3871 gate driver output damage

Question asked by itw-gdc on May 11, 2018
Latest reply on May 11, 2018 by Ding.Li

Hi,

I'm using the LTC3871 in 4 phases configuration to realize a buck/booster 12/24V 100/50A.
I start to debug the board from the boost mode but I have many gate driver output damaged just at switch on without any load.
I have selected the forced continuos current operation tieing the Mode pin to GND.
I have checked my schematics with the demo reference board schematics and I don't see any difference that justify the breaking of the gate driver ouput of the LTC3871.
After the damage the output impedence of the gate driver Top or Bottom is in short circuit (<1 Ohm).
I have two Mos in parallel in each phase with 1Ohm of gate resistance.

Do you have any suggestion in which direction investigate?

Thanks

Giorgio

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