Other Parts Discussed in Thread: DRV8301
Hi,
i am actually facing a problem i have not any idea where it comes from.
I am using the DRV8301 with 6-PWM input. The FETs used are BUK7Y4R8-60E.
My supply voltage range is 22V-25V (Battery). We use a 10Ohms Gate resistor and 0.022µf Charge Pump. The GVDD capacitor is a 2.2µF.
My Problem: The Gate Voltage of the High-Side-FET of Phase B is too low and has oscillations in it. THIS ONLY HAPPENS ON PHASE B. Already changed the FET and checked everything. The other phases are designed the same way.
Following i added some screens from the oscillosopce.
Voltage probe has a gain of 10!!!!
Gate Voltage at High-side switch of Phase B
Another picture of the Gatevoltage of Highside B (does not allways look the same)
Voltage on Phase B
For comparison Gate Voltage on Highside of Phase A
The Lowside Fet of Phase B works fine.
Does anybody have an idea about that?
I will check my BST-signals and maybe change the DRV8301
Kind Regards
Sebastian
