Hello all,
          I'm haing a problem figuring out the best (cheapest) way to
store 1024k x 8 (8Mb) of data for a battery powered data logging
application.  The data doesn't have to be retained on power loss.

I thought the best way to do this would be to use one of the following
SRAM chips:
http://www.cypress.com/cfuploads/img/products/CY62158CV33LL-70BAI.pdf

http://www.samsung.com/Products/Semiconductor/SRAM/LowPower/LowPower_n_LowVoltage/8Mbit/K6X8008T2B/ds_k6x8008t2b.pdf

The application is battery powered and suppose to be small so I don't
care for the second chip much as it seems to be hard to find, very
power hungry while operating and a larger package then the first.

The first chip is excellent, however it's a FBGA and a very small one
at that. So I'm really not sure how I can make a PCB for this with our
standard board house 6mil space/6mil trace.  If I put vias under each
pad the vias will be too big for the pins (my board house's smallest
via is .35mm and the ball diameter is .3mm).  How is mounting of FPGAs
typically done?  Can I put a pad under each outside pin then use vias
in the middle and count on the solder paste on joining the balls to the
vias?  Doesn't seem like a good idea, since the ball will not toush the
via and I'm counting on the solder paste to bridge the gap when it
melts.

OR is there a cheaper way to store all my data than SRAM?

Thnaks in Advance,
Aaron

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