Abstract:A novel low power high-speed true single-phase clockbased (TSPC) divide-by-2/3 prescaler is presented. By modifying the precharge branch in the TSPC flip-flop instead of the AND gate in conventional topologies, the inverter between the two flip-flops of the conventional divide-by-2/3 prescaler is eliminated, and the number of switching stages is reduced to 6. The prescaler is designed in SMIC 0.18 µm CMOS process, the simulating results show that the maximum operating frequency of the prescaler in divide-by-3 mode reaches 10 GHz with 1.836 mW power consumption, and is 50% faster than the conventional divide-by-3 circuit. The maximum operating frequency of the prescaler in divide-by-2 mode reaches 8 GHz with 1.34 mW power consumption.