The Chip you want is the big one, it's about 17mm square has 13 pins each side, the pins wrap under the chip so you need plenty of heat and take your time so as to not strip the solder pads from the board, a hot air rework station is ideal for doing this
The AK90 probably has a connector for the EWS you'll have to make contact with the corresponding contact to the one thats missing in the EWS with the wire that's soldered to the pin that's broken or it's joint with the circuit board.
With luck you should be able to sort it out one way or the other
Russ