So sorry for late response.
About the comment from Andy,
It seems like one of the protection features that could be causing the gate driver to shutdown after the first pulse is the short circuit detection through the DESAT pin. Can't be sure without more information:
- With drain voltage over 400V does the second pulse never appear or does it shutdown earlier than expected?
>> The second pulse never appears.
- Does the first pulse shutdown earlier than expected or does it follow the IN+ input signal?
>>The first pulse follows the input signal. So there is nothing wrong with the first pulse.
- Would you be able to share the gate driver portion of your schematic to see how the gate driver is configured?(Specify if certain components are not populated when running the double pulse test)
>>To disable DESAT function, we remove the capacitor C26 and short the resistor R10.
We don't change other points from the initial setting.
Do you have any oscilloscope capture of the double pulse test you could share?
>>So sorry, it is difficult to share the oscilloscope capture.
- A quick test we could run to confirm if the DESAT pin is causing the gate driver to shutdown would be to disable the DESAT feature. This can be done by shorting the DESAT pin to the COM net of the gate driver IC
>>As mentioned above, we have considered that the DESAT feature was disabled because we shorted the resitor R10.
Is it possible that the DESAT feature is still working in this case? Or any other protections working?
Best Regards,
Teruyuki Ohashi
