I received simple question from my customer, but I don’t have clear answer for it. So please give me your help.
My customer is using LP-creator to make cell ensuring quality due to complying with IPC7351B.
However, she found a difference between LP-creator’s made result and calculated result based on formula of IPC7351B standard as attached file.
In sheet1 of the file, you can see components data sheet as below image. Left side column SODFL package is this example.
Her calculated result by hand is in sheet3 of the file as below. 4.1153mm is Z-dimension and 1.029mm is X dimension, G dimension is 1.029mm.
Also, LP-Creator’s result is in sheet4 of the file as below. 4.2mm is Z-dimension and 1.10mm is X dimension, G dimension is 1.10mm.
So, she would like to clarify reason why such difference is occurred on. Also, would like to request you to let me know how to calculate each cell dimensions in LP-creator.