TPS53355:

Here is the waveform for the same.

Sometimes, Power_Good signal goes high as well, the observation is very random.

Hello,

Usually when Vout is high and working properly, PGOOD should be high too. I suspect this could be measurement error. How are you measuring these signals? Also, how many devices does this occur? just one device? What is the rate of occurrence?

Thank you,

Calan

Hello Calan,

Please accept my apology for delayed response, I missed the response.

This is not measurement error, PGOOD signal is connected to CPLD pin.

we noticed failure on CPLD, so measured this with oscilloscope.
this issue is random in nature, sometimes PGOOD built properly sometimes not.
We are getting this problem in few devices, we got 2 devices those are returned from customer end.

The nature of problem is very random, sometime appear in 4-5 power off ON, sometimes in 40-50 power off-on,

Thnaks

Himanshu