| 摘要 |
<p>Adder of recursive type for calculating the sum of two operands A and B formed respectively of binary data a1, a2, ...an and b1, b2, ..., bn.
<??>An adder having a level NH of recursivity and an order K is denoted ADNH DIVIDED K and comprises according to the invention:
- a first adder ADNH-1 DIVIDED K-1 of order K-1 and of level NH-1 constructed recursively, receiving low-significance operands AL and BL, and delivering an output carry bit COUT and a summation operand SH;
- a second adder ADPNH-1 DIVIDED K-1 of order K-1 and of level NH-1 constructed recursively, receiving high-significance operands AH and BH and the output carry bit (COUT), and delivering a summation operand SH, a carry-propagation bit P, and a carry-generation bit G;
- an overall carry selector (SE) receiving the bits G, P and COUT and delivering an overall carry bit:
CNH DIVIDED OUT = G + P.COUT.
<??>Application to the integrated manufacture of adders of recursive type.
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