Fast design approach for implementing the approximate squaring function

The paper presents a novel method to design the approximate squaring functions. A weighted table is used to derive the Boolean expression for the approximate squaring function which possesses the advantages of less circuit cost, lower power dissipation and shorter critical delay. From the result comparison, the design of 7-bit approximate squaring function only requires 144 MOS transistors which is much less than that required by the other existing approaches. The corresponding MRE (maximum relative error) and ARE (average relative error) are only 16.95% and 5.11 % respectively.