| 摘要 |
An n bit adder includes first computing circuit with 2n inputs for receiving n values of bits of first and second binary numbers and an additional input for receiving an input carry digit. The first computing circuit elaborates from each of the n pairs of bit values of the same significance, a carry digit propagating signal and diagonal generation signals. The adder further including: an estimating circuit performing a first estimation of each coefficient of the number resulting from the sum of the first and second numbers, by using the complement of the corresponding bit of significance of the first number; a second computing circuit, elaborating a set of correcting signals based on the propagating signals and the diagonal generation signals; a correcting block applying to each estimated value of bit of significance k of the sum, k+1 corrections using the correcting signals, and delivering n bits of the sum. |
