Low Power High Speed Multiplier and Accumulator Based on Radix-4 Booth’s Algorithm

With the recent rapid advances in multimedia and communication systems, real-time signal processing like audio signal processing, video/image processing, or large-capacity data processing are increasingly being demanded. The multiplier and multiplier-and-accumulator (MAC) are the essential elements of the digital signal processing such as filtering, convolution, transformations and Inner products. There are different entities that one would like to optimize when designing a VLSI circuit. These entities can often not be optimized simultaneously, only improve one entity at the expense of one or more others The design of an efficient integrated circuit in terms of power, area, and speed simu ltaneously, has become a very challenging problem. P ower dissipation is recognized as a critical parameter in modern the objective of a good multiplier is to provide a physically compact, good speed and low power consuming chip. In this paper, we proposed a new architecture of multiplier-and-accumulator (MAC) for highspeed arithmetic. By combining multiplication with accumulation and devising a hybrid type of carry save adder (CSA), the performance was improved. Since the accumulator that has the largest delay in MAC was merged into CSA, the overall performance was elevated. The proposed CSA tree uses 1’scomplement-based radix-2 modified Booth's algorithm (MBA) and has the modified array for the sign extension in order to increase the bit density of the operands. The CSA propagates the carries to the least significant bits of the partial products and generates the least significant bits in advance to decrease the number of the input bits of the final adder. Also, the proposed MAC accumulates the intermediate results in the type of sum and carry bits instead of the output of the final adder, which made it possible to optimize the pipeline scheme to improve the performance.