Other Parts Discussed in Thread: CSD18532Q5B, CSD18540Q5B
Hello together,
conditions:
DRV8701E + 4x CSD18532Q5B (TI) / NTMFS5C628NLT1G (ON) + 37V DC power supply + DC Motor
Discription:
As a part of our development we have to find some second source components beside the main components. Therfor we measured some different NFETS from different suppliers.
But with all mosfets we have the same problems. They are all dieing (shortcircuit vom drain to source) if we run the motor with pwm less then 100%.
We measured a lot of signals like the gatevoltage, the voltage from U_DS to GND or with an differential probe. We measured the motorvoltage, the current and the power supply. But we see no spikes or extrem voltages/currents.
We changend the IDRIVE level (normaly we use the 25mA/50mA setting) and calculated the level as discribed in the datasheet.
Then we concentrated us from the DRV timings. But all control times are looking good.
We compared the datasheets from the mosfets and we are not sure which value from the second source mosfet is responsible for our problem.
Concrete quenstions:
- Can you analyse our attached dokument/pictures to help us?
- is it possible that the free wheeling diode is responsible for that?
- How important is the value "reverse recovery charge" from the integrated mosfet diode and how he has to be.
- is it possible that the mosfets are dieing because of the "Self On MOSFET Phänomen"?
More infos you can see in the attached dokument. comparison of the mosfets.pdf
Thanks for helping
Regards Boris from Germany