Abstract: A modular multiplication circuit includes a main operation circuit, a look-up table, and an addition unit. The main operation circuit updates a sum value and a carry value according to 2iA corresponding to a first operation value A and m bits of a second operation value B currently under operation, m is a positive integer, i is from 0 to m?1. The look-up table records values related to a modulus, and selects one of the values as a look-up table output value according to the sum value. The addition unit updates the sum value and the carry value according to the look-up table output value and outputs the updated sum value and the updated carry value to the main operation circuit. The modular multiplication circuit updates the sum value and the carry value in a recursive manner by using m different bits of the second operation value B.

Abstract: A modular multiplication circuit includes a main operation circuit, a look-up table, and an addition unit. The main operation circuit updates a sum value and a carry value according to 2iA corresponding to a first operation value A and m bits of a second operation value B currently under operation, m is a positive integer, i is from 0 to m-1. The look-up table records values related to a modulus, and selects one of the values as a look-up table output value according to the sum value. The addition unit updates the sum value and the carry value according to the look-up table output value and outputs the updated sum value and the updated carry value to the main operation circuit. The modular multiplication circuit updates the sum value and the carry value in a recursive manner by using m different bits of the second operation value B.