Approximate Recursive Multipliers Using Carry Truncation and Error Compensation

Abstract

Approximate computing is a fast-emerging paradigm promising higher circuit performances in error tolerant applications. Binary multipliers are a common target for approximate computing due to their complexity and the multitude of their applications. In this paper, we investigate approximate recursive multipliers based on novel 4x4 multiplier blocks. We present three approximate 4x4 multipliers, with different error-precision trade-off, obtained by carry truncation and error compensation. These basic blocks are exploited to design 8x8 approximate multipliers. The proposed circuits are implemented in a 14 nm FinFET technology and show improved performance compared to the state-of-the-art.