identify smd code help me

[Atanas79]

my shaver Philips hq9760 stop work . After open see on pcb blow smd 6pin with code 90bac which is connected to TEA1230TS . Around smd 90bac - have there is a swollen black dot on the body .

After connect li-ion battery 3.5v and start charge - display work and show battery level - and i can start work - but when i disconect charger - - my shaver discharging battery up to 2.5v