SLG3NB148CV / U1900 / MacBook RTC Clock Generator Controller IC
This chip creates the clock signals like SYSCLK_CLK32K_RTC and also the PPVRTC_G3H power rail. It is often placed on the corner of the board making it susceptible to damage.
SLG3NB148CV does NOT work with SLG3NB148V or SLG3NB148A - buy the right chip!
Please check that this is the proper chip for your logic board.