Other Parts Discussed in Thread: TPS65987
Tool/software:
We have a design using the TPS65987 which charges a connected phone when connected to a power supply. The design has worked well, but we've run up against an issue with a newer model phone in the case that the phone battery is completely depleted. The phone will charge from a number of other Type-C chargers, but not from our device. It makes it through the charge negotiation, with our device sending PS_RDY and the phone responding with GOODCRC and charging appears to start, but a little over 2 seconds later a HARD_RESET occurs on the bus and the whole cycle starts over again. I have tested with an older phone (Samsung Galaxy S10e) with a similarly depleted battery, and it does not exhibit this behavior; it charges normally. But when I connect a Galaxy S22, it consistently exhibits this behavior, but only if the battery is severely depleted. I have attempted to attach PD logs from both the working S10e and the non-working S22.
Has this behavior been seen before? Do you have any ideas about what might be causing these hard resets? They do not happen when connecting the phone to a Samsung charger or a generic USB Type-C power supply, but they do happen when I connect the phone to a laptop USB-C port. The problem seems to be with the charger and not the phone.
Thank you for any help you can provide,
Tony
