To replace the chip: 1) Use tweezers to position the chip on the traces. make sure the orientation is the same as it was. 2) Dab some flux on all the pins. Tack down one pin with the iron.3) If the chip is positioned ok over the traces, apply the solder to each pin very briefly. The flux will make it flow nicely without much pressure or time.4) Clean flux with alcohol or acetone and a brush or qtip. Inspect each pin with a mag glass or microscope or loupe to make sure all are soldered and none are bridged.