Low-power application-specific parallel array multiplier design for DSP applications

Digital Signal Processing (DSP) often involves multiplications with a fixed set of coefficients. This paper presents a novel multiplier design methodology for performing these coefficient multiplications with very low power dissipation. Given bounds on the throughput and the quantization error of the computation, our approach scales the original coefficients to enable the partitioning of each multiplication into a collection of smaller multiplications with shorter critical paths. Significant energy savings are achieved by performing these multiplications in parallel with a scaled supply voltage. Dissipation is further reduced when conventional array multiplier is modified disabling the multiplier rows that do not affect the multiplication's outcome. We have used our methodology to design low-power parallel array multipliers for the Fast Fourier Transform (FFT). Simulation results show that our approach can result in significant up to 76% power savings over conventional array multipliers on 64-coefficient FFT computation.