Combining Restoring Array and Logarithmic Dividers into an Approximate Hybrid Design

Abstract

This paper proposes a new design of an approximate hybrid divider (AXHD), which combines the restoring array and the logarithmic dividers to achieve an excellent tradeoff between accuracy and hardware performance. Exact restoring divider cells (EXDCrs) are used to generate the MSBs of the quotient for attaining a high accuracy; the other quotient digits are processed by a logarithmic divider as inexact scheme to improve figures of merit such as power consumption, area and delay. The proposed AXHD is evaluated and analyzed using error and hardware metrics. The proposed design is also compared with the exact restoring divider (EXDr) and previous approximate restoring dividers (AXDrs). The results show that the proposed design achieves very good performance in terms of accuracy and hardware; case studies for image processing also show the validity of the proposed designs.