Title :
Efficient initial approximation for multiplicative division and square root by a multiplication with operand modification
Author :
Ito, Masayuki ; Takagi, Naofumi ; Yajima, Shuzo
Author_Institution :
Hitachi Ltd., Kokubunji, Japan
fDate :
4/1/1997 12:00:00 AM
Abstract :
An efficient initial approximation method for multiplicative division and square root is proposed. It is a modification of the piecewise linear approximation. The multiplication and the addition required for the linear approximation are replaced by only one multiplication with a slight modification of the operand. The same accuracy is achieved. The modification of the operand requires only a bit-wise inversion and a one-bit shift, and can be implemented by a very simple circuit. One clock cycle may be saved, because the addition is removed. The required table size is also reduced, because only one coefficient instead of two has to be stored
Keywords :
digital arithmetic; bit-wise inversion; initial approximation; linear approximation; multiplication; multiplicative division; one-bit shift; operand modification; piecewise linear approximation; square root; Approximation algorithms; Approximation methods; Arithmetic; Circuits; Clocks; Computer errors; Indium tin oxide; Linear approximation; Piecewise linear approximation; Table lookup;
Journal_Title :
Computers, IEEE Transactions on