Asymptotically Zero Power in Reversible Sequential Machines

Conventional methods of energy supply and operation of even CMOS circuits { a technology providing great savings in static energy loss{ are proving to be stumbling-blocks in realizing ultra-dense, petaaop machines, as both energy supply as well as its dissipation pose very diicult problems. Recently several research results have been reported on practical methods and architec-tures for adiabatic operation of CMOS circuits in order to both reduce and reclaim electrical energy in circuits. However, these methods ignore or fail to recover energies supplied to internal capacitances. Moreover, the penalty of \function reversibility" required in these techniques is very substantial in terms of area. We address both these issues with considerable promise of success. Furthermore, we demonstrate that under mild requirements, storage of values is possible without any lower limit on energy dissipation { unlike the limit of 1=2 C V 2 th achieved using a latch suggested in literature.