Carry look ahead addition method and carry look ahead addition device

Abstract

A carry look ahead addition device includes a carry generation/propagation term generator which receives input of two numbers each having a length of n (positive integer) bits and generates the carry generation term and the carry propagation term for each bit, a carry generator which generates a carry for each bit based on the carry input and the carry generation term and the carry propagation term from the carry generation/propagation term generator, and a sum generator. The carry generator receives the carry input and, at the same time, the carry generation term and the carry propagation term are generated at the carry generation/propagation term generator. The carry generator deems the carry input as the carry generation term at the bit immediately below the least significant bit (Bit -1) and the carry propagation term at the Bit -1 to be 0 for processing without a carry input for n+1 bits so as to generate a carry having a length of n+1 bits.

Dependencies are inferred from the claim text.