On 10/10/05, Charles Lepple <[EMAIL PROTECTED]> wrote: > On 10/10/05, John Griessen <[EMAIL PROTECTED]> wrote: > > What is it like hand assembling a BGA package? > > Seems like positioning would be hard to get right > > with no repeatable robot arm to move one thing away > > from the other and check alignment. > > Ideally, the surface tension of the solder helps pull the part into > alignment with the pads, but the amount of misalignment that can be > tolerated is a function of a lot of different variables.
>From my experience, if the board is fluxed with solder, it is almost impossible to align the chip correctly. If you want to hand-solder the chips, the board should be not-fluxed, and should have the sticky SMD patch in place. Well, this was the case for me and I didn't use a liquid solder paste. Maybe it is different if you use the liquid solder paste. vax, 9000 > > -- > - Charles Lepple >
