I knew this would happen. Someone wants to rework a bad BGA artwork by cutting a trace and adding a wire under a 292p 1.27mm pitch PBGA. Has anyone done this before? What kind AND size wire do you use? How do you hold it in place during the replcaement reflow of the component you had to take off to cut the trace and add the wire? How do you keep the newly soldered wire from reflowing an falling off? I have some hi-temp solder I use for profiling but I don't believe I can make a solder joint that will NOT interfere with the collapse of this PBGA component.
I guess I should count my blessings and be thankful it is only 10 PCB's.
Running a wire under a BGA is possible, however if you plan to mount the BGA over the wire you would want to make sure that the wire insulation will withstand the heat of the reflow temperature.
A more reliable way would be to lay a trace between the pads and encapsulate the trace in a high temp epoxy or solder mask.
Precision PCB Services,Inc. performs modifications of this type as intricate as drilling our BGA via's, routing trace through the board and adding pads and circuitry under the BGA package. Even on micro bga.
A challenge for sure. I suggest you review two techniques for this type of rework\modification. The first method uses a special circuit track run out from under the BGA. See: Jumper Wires, BGA Components, Circuit, Track Method at http://www.circuitnet.com/catalog/c6-2-1.htm
The second method is used to add a jumper at a BGA site by running the jumper through a hole in the board. See: Jumper Wires, BGA Components, Through Board Method http://www.circuitnet.com/catalog/c6-2-2.htm
Excellent illustrations included with these procedures.