Tool/software:
My team is using MCT8316ZTEVM for stall torque measurements with duty cycle from 10% to 100%.
Q2 FET that got punctured is part of the Reverse Battery Protection Circuit. My understanding is that Q2 FET gets turned ON if the input voltage polarity is correct.
Can someone help with potential root causes of this failure and how this can be prevented?
Here is failure report data:
The motor current in this report refers to DC or battery current.
- Observed motor current: > 0.16 Amps at 10% Duty cycle and force it was exerting on our force meter 38.5 N
- Observed motor current:> 0.52 Amps at 20% Duty cycle and force it was exerting 89.4 N
- Observed motor current:> 1.2 Amps at 30% Duty cycle and force it was exerting 132 N
- Observed motor current:> 2 Amps at 40% Duty cycle and force it was exerting 166.2 N
- Observed motor current:> 3 Amps at 50% Duty cycle and force it was exerting 223 N
- Observed motor current:> 3.5 Amps at 60% Duty cycle and force it was exerting 264 N
- Observed motor current: > 4.1 Amps at 70% Duty cycle and force it was exerting 310 N
- Observed Motor current: > 4.7 Amps at 80% Duty cycle and force it was exerting 356 N
- Action: We were incrementally increasing the current limit set in DC power supply by 100 mA during every repetition if DC power supply shows Const current mode.
- Result: As soon as we set current limit on DC power supply at 5.5 Amps, and we are testing again on 90% duty cycle abruptly we observed beep sound on Power supply and Spark on TI driver.
Failure Incident
- At 90% TI driver sparked and stop responding.
- There are two punctures observed on TI driver MOSFET Q2 IC.
