A High-Performance Multiply-Accumulate Unit by Integrating Additions and Accumulations Into Partial Product Reduction Process

In this paper, we propose a low-power high-speed pipeline multiply-accumulate (MAC) architecture. In a conventional MAC, carry propagations of additions (including additions in multiplications and additions in accumulations) often lead to large power consumption and large path delay. To resolve this problem, we integrate a part of additions into the partial product reduction (PPR) process. In the proposed MAC architecture, the addition and accumulation of higher significance bits are not performed until the PPR process of the next multiplication. To correctly deal with the overflow in the PPR process, a small-size adder is designed to accumulate the total number of carries. Compared with previous works, experimental results show that the proposed MAC architecture can greatly reduce both power consumption and circuit area under the same timing constraint.