Omid,
I have used the DRS24 for many years and have had similar problems with what you are talking about. I do not have any documents but I will tell you what I have seen. It sounds like an inconsistant collpse of the BGA. If one side of the BGA collpses first, it usually bridges. If the part is uneven, there are usually opens on the lifted side.
Preheat is important. Make sure your preheat is adequate and at the correct temperature before proceding with the profile. Chech your preheater plate for "hot spots" We found certain area's of the plate were hotter. Just make sure that part that you are working on is located over a consistant area. Make sure the correct nozzle is used. A larger nozzle may work but a nozzle that is too small will give you inconsistant results. Verify your temps and airflow. You want the BGA to come up to temperature slowly and consistanly. If the airflow is too high, it will not heat evenly. Air vac should have recommended temps and the air flow should be dependant on the nozzle size that you are using.
Contact Air Vac for recommended times and temps. They have alot of experience and may have the numbers that you need for this part (although this is also dependant on the PCB)
Best of luck
Chris
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Dear sir`s
i want to place one TBGA144 with DRS24 rework st...
- Oct 09, 2009
by
omid
Omid,
I have used the DRS24 for many years and have had s...
- Oct 09, 2009
by
CL
