BQ25750: Chip gets hot when running off battery.

Part Number: BQ25750

Tool/software:

Hi,

Please see the related question for my circuit schematic and other details.

My circuit was running well for a few days but then stopped outputting power even when the battery had lots of charge.  I also noticed that the chip was getting hot and drawing about 60mA from the battery.

After disconnecting the battery and letting the chip cool down, the circuit would once again let power through when the battery was re-connected but the chip still gets very hot.

Also, charging no longer works.

I suspect the chip may be damaged but nothing unusual happened to it.  Just normal battery charge and discharge.  Is there something in my design that might be overstressing it?  The charge current is less than an amp and the max battery voltage is only 29.6V.

In my previous ticket I had noticed the chip running hotter when I switched to the smaller inductor, but that problem had mysteriously disappeared when I tried to reproduce it.  I wonder if it came back and the overheating damaged the chip?   Because the smaller inductor is physically smaller than the one the board was designed for, I have a small piece of wire connecting one leg to its pad.  Perhaps that introduced some instability?

Let me know if there are other measurements I can take.

Thanks,
Phil