Re: low power
well dude.. a circuit can be designed low power by following certain norms..
consider certain factors for low power design such as switchin activity power,short ckt,leakage current and static power dissipation. consider these to evaluate the time averaged power consumption in a circuit further,
methods like
reduction of switching activity by 1- logic restructin , input reorderin, time division multi plexin and glitch reduction by balacin the signal paths would help reductin the switchin activity.
further signal gating, clock gating, use of low power busses - low swign busses, adiabatic computin and DVS - dynamic voltage scaling always helps a lot for this purpose to achieve low power..
jes go thru low power book by gary yeap or anandha chandrasekaran.
these are the very good books for starters.
hope this helps,
with regards,