Novel Low-Complexity and Low-Power Flip-Flop Design

In this paper, a compact and low-power true single-phase flip-flop (FF) design with fully static operations is presented. The design is developed by using various circuit-reduction schemes and features a hybrid logic style employing both pass transistor logic (PTL) and static complementary metal-oxide semiconductor (CMOS) logic to reduce circuit complexity. These circuit optimization measures pay off in various aspects, including smaller clock-to-Q (CQ) delay, lower average power, lower leakage power, and smaller layout area; and the transistor-count is only 17. Fabricated in TSMC 180 nm CMOS technology, it reduces by over 29% the chip area compared to the conventional transmission gate FF (TGFF). To further show digital circuit/system level advantages, a multi-mode shift register has been realized. Experimental measurement results at 1.8 V/4 MHz show that, compared with the TGFF design, the proposed design saves 64.7% of power consumption while reducing chip area by 26.2%.