Datapath layout compiler using bit-wise cell-sizing scheme for delay balancing and power minimisation

Abstract

While existing datapath compilers generate the same size buffer for all bits, in real datapaths, the load capacitance fluctuates according to the bit position, which leads to a nonuniform bit delay with unnecessarily high power consumption. This Letter proposes a datapath layout compiler using a bit-wise cell sizing, scheme that reduces the power consumption by equalising the delay of each bit position to the critical bit delay. Experimental results using the example of a real microprocessor have demonstrated a power consumption saving using the tri-state bus of 12% on average, compared to conventional datapaths using a uniform-size cell.