How to give values for SMD pad creation, NSMD pad creation? I know for NSMD pad creation we might take land pattern less than ball diameter, also we want to give soldermask opening for NSMD pad.
For example, I have a ball diameter of 0.5 mm, then I should take 0.4 nominal land pattern and soldermask opening is 0.627 — is this right? If it is wrong, then please guide me, and also explain SMD pad creation.
Here I attached one image, in this they given ball diameter (or land pattern?) for BGA. Kindly clear my doubt. If it is ball diameter then I have to take land pattern less than from given value. I am confused in this — is that ball diameter or ball land pattern? Kindly excuse me on my mistakes of language. i added one more picture here is this is lanpattern or not