ROM-Based Logic (RBL) Design: A Low-Power 16 Bit Multiplier

We present a ROM-based 16 times 16 multiplier for low-power applications. The design uses sixteen 4 times 4 ROM-based multiplier blocks followed by carry-save adders and a final carry-select adder (all ROM-based) to obtain the 32 bit output. All ROM blocks are implemented using single transistor ROM cells and eliminating identical rows and columns for optimizing the power and performance. Measurement results in 0.18 mum CMOS process show a 40% reduction in power over the conventional carry-save array multiplier when operated at its maximum frequency. The ROM-based design also provides 44% less delay than the array multiplier with a minimal increase (7.7%) in power. This demonstrates the low-power operation of the ROM-based multiplier also at higher frequencies.