Analysis and optimization of leakage current characteristics in sub-65 nm dual Vt footed domino circuits

The inputs and clock signals combination sleep state dependent leakage current characteristics is analyzed and the optimal sleep state is examined in sub-65 nm dual Vt footed domino circuits. Simulations based on 65 and 45 nm BSIM4 models show that the conventional CHIL state (the clock signal is high and inputs are all low) is ineffective for lowering the leakage current and the conventional CHIH state (the clock signal and inputs are all high) is only effective to suppress the leakage current at high temperature other than the high fan-in domino circuits. For the high fan-in footed domino circuits at high temperature and most of footed domino circuits at room temperature, the CLIL (the clock signal and inputs are all low) state is preferable to reduce the leakage current. Further, the influence of the process variations on the leakage current characteristics of the dual Vt footed domino circuits is also evaluated. It is observed that the average leakage current is universally higher than the date reported in the normal corner and the CLIL state is the optimum choice considering the leakage current reduction and the robustness to the process variations simultaneously.