Hum, I think I have it identified. The form factor was wrong, it's not a SOT23-6.

The IC in question seems to be MUN5314DW1, SOT-363....

Yea I reckon most get swapped out due to permanent firmware kills. The reason I'm asking though is I'm working on a number of P190 batteries. What's nice about them is that they run Attiny88's as the brain, and even nicer thing is that the protection fuses are not blown, so both the flash and the eeprom can be read. I'm trying to figure out of the firmware kill can be removed and in the process I'm creating schematics of the whole board. There's only a few components on the board I don't recognize, and U4 and U5 are currently the most interesting....