| 摘要 |
PURPOSE: To constitute the p-root tree of an order (n) by combining functions respectively inputting three operands corresponding to operands and reducing them to be two operands corresponding to carrying and adding results so as to form two outputs. CONSTITUTION: Tree structure includes carrier save adders A1,...A16. Each adder A1,...A16 accepts the three operands corresponding to three partial products or the operands given from another adder A1,...A16 to respectively three inputs, and reduces these operands to be two operands corresponding to the carrying and adding to respectively give to the two outputs. These tree adders A1,...A16 are paired and four operands accepted to four inputs 60 to 63 by each pair R1 and R'1 or ...R3 constituting the reduction assembly of four inputs are reduced to be two operands to give to two outputs 65 and 66, respectively. One tree gives two outputs two operands, namely an operand corresponding to the sum of the partial products of multiplying and an operand corresponding to carrying. |
