Patent ID: 7257609

Claim:
A multiplier device, for multiplying a multiplicand by a multiplier represented by multiple canonic signed digits, comprising: a storage for storing a number of pieces of information corresponding to the multiple canonic signed digits of the multiplier wherein each of the number of pieces of information stored in the storage includes a shift control signal of B bits width which represents the value of a significance of a concerned digit of multiplier, a sign-flag indicating whether the concerned digit of the multiplier has a value of +1 or −1, and a zero flag indicating whether the concerned digit of the multiplier has a value of zero or not; a shifter for shifting the multiplicand based on the shift control signal; and an adder and wherein; an output of the shifter is added by the adder to an output of the adder obtained previously, wherein the pieces of information in the storage are sequentially read out, and wherein the sign-flag and the zero-flag are supplied as control signals to a signal processor which outputs a 2's complement of the multiplicand.