Kieran,

I have a similar problem, I'm running my 16LC76s on 5 V supply and
talking to 3.3V MMC card.

I use a 74LVC14 buffer to let the 5 V pic drive the 3.3 V card.  But
you still need two supplies.  For me, that was OK, since a had a
seperate regulator with shutdown for the card slot.

Good luck!

Barry.
------------
Barry King, KA1NLH
NRG Systems "Measuring the Wind's Energy"
http://www.nrgsystems.com
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