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Sorry the application may not be suitable to reveal in forum. The input voltage to TPS63020 is at 2.8V RMS with fluctuations between 2.6V(min) to 3V(max) during board operation. The output of the converter is set to 3V and the measured load current on the rail is approximately 0.8A RMS with frequent instances of peak current hitting 2.3A. One out of several boards reset after stress test >24 hours. The issue on that board was traced to the PG (power good) pin having a momentarily voltage drop (few microseconds) which caused subsequent converters in the power sequence chain to shutdown(PG of TPS63020 connects to EN of second converter). I suspect the culprit may be the high temperatures on the board during the stress test and the converter hitting its current limit. The challenge is to find a method of configuring the TPS63020 or even an alternate converter that meets the input and output voltage/current requirements. Also the converter and inductor needs to be within 1.5mm of height. The inrush current during start-up must not be too high. I am thinking of using two TPS63020 to power separate portions of the board and synchronize them 180 degrees out of phase so that the in-rush current is minimum. How better can we tackle this problem please?

The TPS63020 might be ok under these conditions, did you follow the layout and thermal recommendations as in the datasheet? Up to what temperature are you measuring?

As die temperature increases, the dynamic current limit of the TPS63020 decreases. The dynamic current limit also decreases as VIN drops. Have you verified the TPS63020 input voltage is maintained? If the TPS63020 is limiting the current for one of the aforementioned reasons, the output voltage will start dropping and PG will be asserted low. What rail are you pulling PG up to? Have you verified that this PG rail is not the issue?