98512B EWX Charging iC

Samsung S9, S9+, and Note 9 boards commonly develop charging faults after power surges, liquid exposure, or a failed charging port replacement. The 98512B EWX steps in as the charge-control IC on these boards, sitting between the USB input and the battery power path. When this chip degrades, your customer reports a phone that shows the charging icon but never fills up, or one that stays completely dead after flash and needs a jumper before it responds at all.This IC belongs to the MAX98512 family used across the Exynos and Snapdragon variants of the S9 line, so board revision matters less than most technicians expect — the chip carries the same footprint and function across G960F, G960U, G965F, and G965U boards. You get a drop-in BGA part rather than a full board swap, which keeps repair cost down for the shop and turnaround time short for the customer.Diagnosing this fault starts on the bench, not with software. Check current draw on a bench power supply first — a board pulling near-zero current with a good battery and cable usually points straight at this charging IC rather than the charging port or battery connector. Compare against a known-good board's boot current if you keep reference notes, since a genuine 98512B fault reads distinctly different from a battery connector short or a dry-joint tristar issue.Removal and reball follow standard BGA workflow. Preheat the board on a hot plate to reduce thermal shock, apply flux generously around the chip, and lift with hot air at controlled temperature rather than forcing it with a blade. Clean the pad thoroughly before placing the new IC — leftover solder bridges are the single most common cause of a "fixed" board that still won't charge. Reball with the correct paste size for this chip's ball pitch, then reflow under the microscope so you can confirm alignment before the board goes back together. A misaligned placement here shows up later as intermittent charging rather than a clean pass or fail, which wastes more bench time than getting it right the first time.Once reflowed, test with a known-good cable and charger before reassembly. A board that charges cleanly on the bench but fails after the case is closed usually points to a pressure issue on an adjacent connector, not this IC — worth ruling out before you reopen the board unnecessarily.Keep a few of these in stock if Samsung S9/S9+ repairs come through your shop regularly. Dead-charging complaints on this model line are frequent enough that having the part on hand, rather than ordering per job, saves a full day of customer wait time on a repair that otherwise takes under an hour on the bench.