Design of low-power high-radix switch fabric with partially-activated input and output lines

A low-power radix-64 switch fabric that achieves more than 10× reduction in power compared to a basic matrix-type implementation is presented. Such a dramatic reduction in power is enabled by partially activating the high-capacitance input and output lines and therefore keeping the switched capacitance small when propagating the signals. For instance, each of the input line is divided by 8 repeaters. Also, each output line is divided into 16 sub-sections, each of which can be routed to the final output port via a hierarchical 16:1 output multiplexer. Based on the transistor-level simulations taking the wire loading into account via detailed floorplanning, the switch core implemented in 45nm CMOS is estimated to have 25-FO4 latency while dissipating only 81-mW.