| 摘要 |
PCT No. PCT/EP92/02350 Sec. 371 Date Jun. 20, 1994 Sec. 102(e) Date Jun. 20, 1994 PCT Filed Oct. 12, 1992 PCT Pub. No. WO93/08523 PCT Pub. Date Apr. 29, 1993.A one-bit adder includes a carry stage and an adding stage and is constructed in a fast CMOS complementary pass transistor logic with complementary analog CMOS switches in the adding stage which consist of a PMOS and an NMOS transistor. The source of the PMOS transistor is connected with the drain of the NMOS transistor and the drain of the PMOS transistor is connected with the source of the NMOS transistor. The gate of the PMOS transistor receives inverted signals with respect to the gate of the NMOS transistor. Two partial output sum signals are generated by two of the switches which are connected with the input and with the output, respectively, of an inverter and the output sum signal of the adder is available at the output of the inverter. A fast multiplier includes (i) a plurality of the above fast one-bit adders, (ii) reduction of partial products by application of a Booth-McSorley process, (iii) diagonal propagation of caries from one partial product to another allowing all sums on one line to be done simultaneously, and (iv) application of a carry select approach in the final 14 bits and in the first two adders in intermediate rows.
|
