Intermittent Resonant Clocking Enabling Power Reduction at Any Clock Frequency for Near/Sub-Threshold Logic Circuits

In order to eliminate the limitation of a narrow frequency range of conventional resonant clocking, intermittent resonant clocking (IRC) is proposed for near/sub-threshold logic circuits. In this paper, IRC is applied to 0.37 V 32-bit adder array with latches and adder array with flip-flops fabricated in a 40 nm CMOS process. Measurement results show that IRC reduces the clock power by 36% at 980 kHz and the clock leakage power by 81% compared with conventional non-resonant clocking when IRC is applied to the adder array with latches. The same power reduction is achieved when IRC is applied to the adder array with flip-flops. IRC can reduce the clock power at any clock frequency, which enables flexible selection of the clock frequency.