Integrated Power and Clock Distribution Network

In this brief, we investigate and propose solutions for integrating the clock and power distribution networks all the way to circuit level. The aim is to reduce metal requirements, routing complexity, and power. The concept of an integrated power and clock distribution network (IPCDN) is proposed in order to eliminate the need for the global and local clock distribution networks. In IPCDN, a differential power-clock signal (P_wr_C_lk) with a suitable dc voltage level and sinusoidal voltage-swing feeds the VDD ports in combinational and sequential elements. A clock buffer is used for sequential elements in order to extract a full-swing clock from the differential P_wr_C_lk+ and P_wr_C_lk- signals. IPCDN does not require any change to be made to the conventional combinational and sequential circuit design. The proposed elements of IPCDN, including the LC differential P_wr_C_lk driver and the clock buffer, have been simulated using Taiwan Semiconductor Manufacturing Company 65-nm CMOS technology with a P_wr_C_lk signal, a 1-V dc component, and 400-mV sinusoidal swing at a frequency of 5 GHz. In addition, the behavior of a master-slave flip-flop with IPCDN was investigated at extreme corners. Simulation results demonstrate correct functionality of all elements of the IPCDN. Comparing IPCDN to a buffered square-wave clock distribution network illustrates that, with a heavily loaded network, IPCDN achieves around 20% reduction in power. This percentage increases when the network capacitance is dominating.