Other Parts Discussed in Thread: CSD88599Q5DC, DRV8323
Hello!
My name's Pedro and recently we've had issues with drivers burning and bursting the IC, here's a picture:
As you can see the IC is broken, and the xray reveals the soldering was correct.
I've calculated the IDRIVE settings for our mosfets (CSD88599Q5DC) with a Qgd = 7nC following TI recommendations of having 100nS of rise/fall times.
7nC / 100nS = 70mA. (1)
At the moment I have ~1A in N-current and ~500mA for P-current. With those currents I can measure ~50nS in rise/fall times with an osciloscope.
So my questions are:
1) Is it possible that 50nS in rise/fall times are fast enough to induce such a ringing that burns the driver/fets?
2) If I lower the IDRIVE settings to ~500mA in N-current and ~250mA for P-current I can measure rise/fall times of 100nS. Should I follow the calculations in (1) or should I use the ones I actually measured 100ns?
3) What else could be the cause of this driver breaking? We don't have temperature problems.
4) I've tried measuring shoot-throught but it seems impossible given the EM noises I get in the osciloscope. Do you have any recommendations for this measurement?
Thank you very much.
Best regards.
P.S.:
Deadtime = 400nS
Vbus = 36V
Nominal motor power = 250W
