[eagle] Re: BGA Tools

[Lyle Johnson]

> Besides, I wouldn't send out a single BGA-containing board to my
> TERRESTRIAL customers without having it X-Ray scanned first to check the
> connections.  I certainly wouldn't send one into space without a scan. 
> Are you planning on purchasing an XRay machine as well?

No, no plans on an X-ray machine, Matt.    High-volume manufacturers of 
boards with BGAs dont; X-Raythem either.

Once you get the thermal profiles worked out, it makes reliable connections.

The equipment comes with a test board for 4 positions, and 4 BGA devices 
that contain a pattern of jumpers so that you can determine when it is 
in fact properly soldered down.  This helps to calibrate the thermal 
profiles.

This is the same machine JPL used to place the BGAs in the Spirit and 
Opportunity rovers.  Not sure if they X-rayed these or not, but it is 
the same exact placement tool set.  In fact, Zephyrtronics includes a 
NASA report on how to use the machine for reliable placements.

Lyle