Hi, For the unit's that have failed, can you please check the output to see if there is an opposite polarity pulse every 128 clock cycles? It would be helpful to check exact AVDD signal by short probe ground or COAX connection across C33 to confirm the magnitude of the high frequency ringing. Assuming that this ringing on AVDD (either coupled or conducted) from the gate driver is causing this issue to occur, a snubber or capacitance multiplier on the AVDD circuitry to increase robustness of the AVDD line may be helpful. This would help from the AMC side, but likely best course of action would be to find the cause in the bridge circuitry for this ringing and try to improve settling.
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