DESIGN OF TAPERED BUFFERS WITH LOCAL INTERCONNECT CAPACITANCE

This paper presents a design methodology and analytic relationships fo r the optimal tapering of cascaded buffers which consider the effects of local interconnect capacitance. The method, constant capacitance-to -current ratio tapering (C3 RT), is based on maintaining the capacitiv e load to current drive ratio constant, and therefore, the propagation delay of each buffer stage also remains constant. Reductions in power dissipation of up to 22% and reductions in active area of up to 46%, coupled with reductions in propagation delay of up to 2%, as compared with tapered buffers which neglect local interconnect capacitance, are exhibited for an example buffer system.