Other Parts Discussed in Thread: UCC28780
The measure resistance on VREF pin is 28 ohms. We think UCC282780's VREF was damaged internally as all other external components connected to VREF are OK.. What condition would cause the damage?
EVM module's VDD stays around 45ms of ramp-up period where VREF is 0V. Is 150ms of VDD ramp-up period for our design OK ?