iPhone 8 8P U5890 fingerprint power supply 2.75V How to replace iphone iC chips? *Remove the chip cleanly, with hot air. *Clean the tracks with a soldering iron, tin and flux. *Clean the map. *Inspect the card under the microscope. *If we compare to the diagram on the PhoneBoard software;We observe very clearly that we will be able to put a wire to redo this connection. *Put on some flux. *Take a soldering iron with tin at the end. *Pass over the chip to smooth the balls. *Clean. *Put on a reballing stencil. *Spread some soldering paste. *Heat with hot air to form the balls. *Extract the chip by pushing with a thin tweezers. *Check the size of the balls. *And we end up putting the chip back. Flow, position and solder with hot air. *We let the phone cool, we go back and the problem is solved!