Re: BGA packages in high vibration environments

Xpost 2 cae and caf, no Fup.

Hallo,

"Geoffrey Mortimer" wrote:

Actually that's a very hot topic as BGA seems to get usual in the world of FPGAs and ASICs. I know that our mechanical engineers allready research on this topic, as we are very likely to have some fine pitch BGA in a high vibration environment in future. I would guess, that you should ask in some mechanical newsgroups as well. A big problem using FBGA is the test, wether you connected all balls proberly [1], as you have no chance of easy visual inspection.

bye Thomas

[1] in a mechanical aspect. Of course you get a quick answer if one IO has no electrical connection.

--
Don't answer to the email in from, use thomas[at] for
PM.

I recently saw a product that allows visual inspection of the solder balls on a mounted BGA. It is a fiber optic microscope and has tiny fiber probes that can run between the balls. I'll look for the info if anyone is interested.

--

Rick "rickman" Collins

rick.collins@XYarius.com
Ignore the reply address. To email me use the above address with the XY
removed.

Arius - A Signal Processing Solutions Company
Specializing in DSP and FPGA design      URL http://www.arius.com
4 King Ave                               301-682-7772 Voice
Frederick, MD 21701-3110                 301-682-7666 FAX

Followup to: By author: rickman In newsgroup: comp.arch.fpga

A lot of people seem to do X-ray inspection, which I guess could be considered "visual" in some way.

-hpa

--
 at work,  in private!
If you send me mail in HTML format I will assume it's spam.
"Unix gives you enough rope to shoot yourself in the foot."
Architectures needed: ia64 m68k mips64 ppc ppc64 s390 s390x sh v850 x86-64

Rick,

I'd certainly be interested in more info on the fiber microscope you mentioned. Debugging designs with lots of big BGAs is tough enough without wondering whether it's an assembly issue or not, and traditional xray techniques are good for showing shorts, but no so good for opens ...

----- R> >

high

There's also JTAG tools that can read and write arbitrary values to I/O pins. Roughly $1K for benchtop systems, $10K for a production tester. If the BGA is hooked to other chips with JTAG, you can make a rather complete test.

And of course there's traditional bed-of-nails, not used much due to cost of implementing on proto hardware.

Dave Kinsell

Sorry I did not get back to you sooner. The original contact was ASG at

They make the IS-1000 which gets under the BGA from what I can see. So you can see each and every ball. But you should get a demo since the sales pictures don't clearly indicate if they are looking at the edge row of balls or an inner row.

With a google search I found this -

They seem to make a similar product, but the web page is not too clear if they are just looking at it from the outside.

R>

--

Rick "rickman" Collins

rick.collins@XYarius.com
Ignore the reply address. To email me use the above address with the XY
removed.

Arius - A Signal Processing Solutions Company
Specializing in DSP and FPGA design      URL http://www.arius.com
4 King Ave                               301-682-7772 Voice
Frederick, MD 21701-3110                 301-682-7666 FAX