I am using TEA1721AT for three phase SMPS in motor control panel. I designed and tested it in lab upto 4KV. But it get damaged. Foe designing I had used reference design UM10520.
I designed this for 1200VDC and test up to 700VAC using auto transformer. I only make change that removed 150V zener/TVS diode. Other devices with same design are working on field very well.
I want to know what are the reasons that IC may get damage or burnt out. I am sharing the field situation so that you can better give us solution -
1. IC damage after devices get settled so no chance of start surge.
2. We have given enough thermal pad. you can judge with photo I attach.
3. Is high voltage is the issue? If it is then what its maximum range. Please keep in mind I had test it with 1000VDC with load for a enough time.
Waiting For reply.
Thank you.