SN0903048 U5010 SMC ON IC
SN0903048 U5010 is a chipset which controls the SMC to turn on. SMC is usually located towards the corner. Which makes it prone to any physical or liquid damage.
SMC will not turn on if the SMC_RESET_L is not present. SMC_reset_L is either LOW or zero volts. SMC reset low signal means active signal where zero reading means no signal. LOW stands for low signal. If SMS reset is LOW, SMC will be “reset”. Basically, SMC should not be turned on until the power rails have stabilized. This IC ensures that the PP3V42_G3H 3.42v power rail has stabilized prior to allowing SMC_RESET_L to go high.
Check the pull-up resistor for SMC_RESET_L that pulls SMC_RESET_L up to 3.42v before replacing this IC. If removing this IC does not bring SMC_RESET_L up, then replacing this chip will not fix your logic board issue.
The job of this chip is not to “create” SMC_RESET_L, but rather, to keep it LOW(0v), in reset mode, until the power rail has stabilized. If you remove this IC and SMC_RESET_L is still low, you either have an issue with the SMC pulling the voltage down, or the pull-up resistor is creating the signal.
Sometimes a faulty or water damaged keyboard can reset SMC, so please disconnect the keyboard from your logic board and see if this fixes the SMC issue without replacing the chipset.
Compatible with logic boards listed below
820-3023 820-3209 820-3332 820-3024 820-3208 820-3462 820-3330 820-2915 820-2879 820-3115 820-2936