M. Nogawa et Y. Ohtomo, A DATA-TRANSITION LOOK-AHEAD DFF CIRCUIT FOR STATISTICAL REDUCTION INPOWER-CONSUMPTION, IEEE journal of solid-state circuits, 33(5), 1998, pp. 702-706
A new data-transition look-ahead DFF (DL-DFF) that reduces the power c
onsumption of CMOS LSI's is proposed. The power consumption is reduced
in accordance with the data-transition probability, The main feature
of the DL-DFF is that the clock signal is deactivated when there are n
o data transitions. This reduces the power consumption when the data-t
ransition probability is low. The power consumption of a DL-DFF is com
pared to that of a conventional one by measuring a test chip fabricate
d using a 0.25-mu m CMOS/SIMOX process. It is found that a DL-DFF cons
umes less power than a conventional one when the data-transition proba
bility is under 60%. For example, when the data-transition probability
is 25%, it consumes 29% less power, Moreover, some suitable applicati
ons of a DL-DFF are presented.