Near-threshold adiabatic flip-flops based on PAL-2N circuits in nanometer CMOS processes

This paper presents ultra low-power adiabatic flip-flops that operate on near-threshold region. The near-threshold flip-flops are realized by PAL-2N (pass-transistor adiabatic logic with NMOS pull-down configuration) circuits. A near-threshold mode-10 counter is verified. All circuits are simulated using NCSU PDK 45nm technology by varying supply voltage from O.2V to O.9V with O.1V steps. Based on the simulation results, the adiabatic flip-flops that operate on medium-voltage region can not only keep reasonable speed but also reduce greatly energy consumptions.