Dear TI team,
I am using Dual channel gate driver IC "UCC21520AQDWRQ1" to drive MOSFETs of Phase Shifted Full Bridge Topology (Input voltage is 400 Vdc and output voltage is 175 Vdc). During turning-off of the MOSFET, I have observed spike in Vds of the MOSFET. Similar spike with lower amplitude is observed in VGS pin of the MOSFET which is connected to IC (OUTA pin). Strangely, I am observing this spike on input pin of IC (INA pin). This spike is as large 7V, nominal voltage applied to pin INA is +3.3V. As INA pin is connected to microcontroller PWM pin, it is getting damaged due to +7V spike.
Since, driver IC "UCC21520AQDWRQ1" has reinforced isolation of 8kV, Is there a possibility that spike is getting transferred from OUTA pin to INA pin via isolation?