Looking for people who solder laptop chips with hot air Hello !
i am looking for people who solders NVIDIA, ATI and other laptop chipsets with hot air rework stations.
i am using ok industries 3500 bga rework station. (metcal)
but lot of chipsets are overheated when desoldering with original lead fre solder from factory. for example:
to desolder chip GF-GO7600-H-N-B1 (DV9000) 3.5cm x 3.5cm i use homemade nozzle 3.7cm x 3.7cm
not to damaged motherboard, need to use profile:
260c from bottom (±180c mesured on pcb)
soak from top 150sec 230c
peak 180sec 360c.
but on the end i hear "pop" sound and i see crack around the chipset crystal.
----------------------------------------------------------------------------------------
If i take new chipset and reball it with solder balls Sn63Pb37
then all ok, from bottom 260c, from top 230c and solder melts.
i need advices. thank you all... |