Everybody aware of the tomb-stone problem on 0402 package. I've done everything I could i.e. Profile, placement, 10 Deg placement, stencil design, but still this culprit exist. One things for sure is taht I have a very bad pad size for 0402 ( 25 mil X 27 mil with the gap of 16 mil ), but before I propose the change in land size, there is one concern that I have over my oven. The oven used is 3 zones oven. What does this effects Tomb-Stoning comparatively if they were run on 7 or 8 zone oven. ( Flexibility in profiling ? )
2nd Question, I used to work with oven with non-adjustable air. The machine's has their own amplifier that amplifies the required amount of air. Theoven that I'm working on now, has regulators with mercury indicators. How do I know what is the best setting for "these" air, in order to get the best out of my machine before concluding that my current machine is a piece of crap.
Inputs are welcome. Thanx.
danial
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