Multiplier circuit comprising a plurality of multiplier segments

摘要

A multiplier circuit comprises a plurality of multiplier segments each receiving operand words of a first length and input selectors, e.g. input Sel which can be high or low, which select a first set of inputs when the multipliers are to operate individually and a second set such that the multiplier segments are concatenated to form a wider multiplier operating on operands of a second word length. The circuit is used as a secret key multiplier to implement a wider width key in programmable encryption.