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Radix-4 Square Rot Without Initial PLA
August 1990 (vol. 39 no. 8)
pp. 1016-1024

A systematic derivation of a radix-4 square-root algorithm using redundant residual and result is presented. Unlike other similar schemes it does not use a table lookup or PLA for the initial step, resulting in a simpler implementation without any time penalty. The scheme can be integrated with division and incorporates an on-the-fly conversion and rounding of the result, thus eliminating a carry-propagate step to obtain the final result. The result-digit selection uses 3 bits of the result and 7 bits of the estimate of the residual.

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Index Terms:
redundant result; on-the-fly rounding; radix-4 square-root algorithm; redundant residual; division; on-the-fly conversion; result-digit selection; digital arithmetic; logic arrays; number theory.
M.D. Ercegovac, T. Lang, "Radix-4 Square Rot Without Initial PLA," IEEE Transactions on Computers, vol. 39, no. 8, pp. 1016-1024, Aug. 1990, doi:10.1109/12.57040
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