BGA crack and strain gauge measurement

Subscribe to Thread

Dear all, I have an issue here where we found BGA crack. ... - Nov 25, 2006 by Sean

There is no standard for a strain gage measurement of allowa... - Nov 27, 2006 by davef

Dear Davef, Thanks for your input...The crack happen at t... - Nov 29, 2006 by Sean

Sean

#45599

BGA crack and strain gauge measurement | 25 November, 2006

Dear all,

I have an issue here where we found BGA crack. Understand from friend, we need to study any possiblity of our own jig or fixture cause this problem via strain gauge measurement..My question: Is there any standard @ specification established for each strain gauge measurment in order to us to know on whether this measured value is acceptable or not. In others word, what is the acceptable upper limit for strain gauge value in order to judge the jig or fixture is still acceptable?

Thanks for participants.

reply »

davef

#45635

BGA crack and strain gauge measurement | 27 November, 2006

There is no standard for a strain gage measurement of allowable deflection of a board or a fixture.

It's possible that your fixture is causing the BGA cracking that you see. What protion of the BGA is cracking? If it is the solder connection, search the fine SMTnet Archives for background discussion on common responses: * Reflow recipe [reflow profile] * Potato chip* * Coefficient of thermal expansion (CTE )

reply »

Sean

#45740

BGA crack and strain gauge measurement | 29 November, 2006

Dear Davef,

Thanks for your input...The crack happen at the pad/solder ball interface..Pls review the new thread that I post just now with title called "BGA BALL CRACK AT PAD/SOLDER BALL INTERFACE"

Thanks!

reply »