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BGA Requirements
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BGA Requirements

by IHeartEngineering on Sun Aug 28, 2011 5:19 pm

What equipment/techniques are required to build production quality boards with BGA parts?
We have 20-40 boards to build with one 32-Lead Ceramic Ball Grid Array part per board.
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Re: BGA Requirements

by adafruit on Sun Aug 28, 2011 5:22 pm

well what failures are you seeing? :)

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Re: BGA Requirements

by IHeartEngineering on Sun Aug 28, 2011 5:49 pm

Since each part is over $25, I'd like to have zero failures.
What kind of failures should we expect if we hand place the parts using a microscope with a tacky flux?
With the rest of our board we have been getting 95+% good parts with solder paste, reflow and a touch of hand rework now and again.
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Re: BGA Requirements

by adafruit on Sun Aug 28, 2011 6:36 pm

it really depends completely on how good you are with hand placement. you're probably going to have to bite it and just try placing a few.

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Re: BGA Requirements

by mikeselectricstuff on Mon Aug 29, 2011 4:56 am

Practicality depends on the pitch, but you need to have a good quality paste print (stainless stencil, inspect every one with a microscope ), and accurate placement, straight-down with no sideways wobble splurging the paste across pads- you may need some mechanical aid for this.
Also probably worth putting alignment marks on the copper layer (not silkscreen as alignment can be poor)
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Re: BGA Requirements

by blogger on Wed Aug 31, 2011 12:58 am

Sounds like Analog's gyros.
Good luck.
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Re: BGA Requirements

by IHeartEngineering on Wed Nov 09, 2011 4:00 pm

I can now report that it is possible to hand place BGA parts if you use a stencil to apply solder paste. I'm not convinced you can do it without a stencil.
We have managed to achieve a 100% success rate with a sample set of two boards. ;)

pbrd-01.jpg
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If anyone is interested I can post a photo of our stencil setup.

Does anyone have a good technique for low volume underfill for BGA parts?
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Re: BGA Requirements

by Rochey on Thu Nov 10, 2011 3:54 pm

Please post the stencil setup :)

thanks!

Rochey
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Re: BGA Requirements

by IHeartEngineering on Thu Nov 10, 2011 6:13 pm

The jig is a bunch of 'scrap' boards blue taped down to an anti-static mat with a bluetape hinge to hold the stencil in place.
The stencil alignment was checked with a microscope. This is probably the easiest solution that provides the minimum quality required.

ballin-01.jpg
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ballin-02.jpg
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ballin-03.jpg
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Re: BGA Requirements

by IHeartEngineering on Thu Nov 10, 2011 6:13 pm

ballin-04.jpg
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Re: BGA Requirements

by IHeartEngineering on Thu Dec 08, 2011 2:57 pm

Has anyone reballed a BGA component?
Tips or tricks?
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