BZ-FAD: A Low-Power Low-Area Multiplier Based on Shift-and-Add Architecture

In this paper, a low-power structure called bypass zero, feed A directly (BZ-FAD) for shift-and-add multipliers is proposed. The architecture considerably lowers the switching activity of conventional multipliers. The modifications to the multiplier which multiplies A by B include the removal of the shifting the B register, direct feeding of A to the adder, bypassing the adder whenever possible, using a ring counter instead of a binary counter and removal of the partial product shift. The architecture makes use of a low-power ring counter proposed in this work. Simulation results for 32-bit radix-2 multipliers show that the BZ-FAD architecture lowers the total switching activity up to 76% and power consumption up to 30% when compared to the conventional architecture. The proposed multiplier can be used for low-power applications where the speed is not a primary design parameter.