A true single-phase clocked flip-flop with leakage current compensation

Abstract

A true single-phase clocked (TSPC) flip-flop, which compensates for the leakage current generated at dynamic nodes, is proposed to cover a wide operational frequency range in submicron CMOS processes. To implement the proposed TSPC flip-flop, three feedback circuits composed of a gated inverter (GI) are added to the conventional TSPC flip-flop. The GI is controlled by a clock and the internal signal of the conventional flip-flop, without an external control signal or a complementary clock signal. Furthermore, the strength ratio of the normal path to the feedback path does not need to be considered for the proposed TSPC flip-flop since the feedback circuit is only enabled when the dynamic node acquires a floating state. The proposed TSPC flip-flop is designed using a 1-poly 6-metal 65nm CMOS process with a 1V supply voltage. The simulation results show that the proposed TSPC flip-flop, which is optimized for normal operation at an operational frequency of 2 GHz, exhibits an error-free operation at low operational frequencies such as 1MHz. The three added feedback circuits increase the power consumption by 8.8% as compared to that of the conventional TSPC flip-flop and occupy 12.28% of the proposed flip-flop.