We are attempting to use the TPS2413 ICs for a UPS circuit. The battery power source is a 12V battery (operates at ~13.6V), and our main power supply source which is 15V.
The TPS2413 at (U4) which is regulating the Battery power source fails after a few months of operation.
We have a 2200 capacitor between terminals A & BYP, and in the scenario where the chip fails, we are able to recover functionality temporarily by draining the capacitor (shorting A to BYP). But once all power is shutdown to the system, and restarted, it again goes into a failed state (always open).
If we replace the TPS2413 chip with a new IC, the system is fully functional again.
We have a few hundred boards built to date which are exhibiting the same problem.
I've attached our schematic.
Can anyone help us understand what we might be doing wrong?