In one embodiment, a circuit arrangement for performing cryptographic operations is provided. The circuit includes a substitution block, a cryptographic circuit coupled to the substitution block, and a balancing circuit coupled to the substitution block. The substitution block includes a memory unit storing substitution values and ones-complement values that are corresponding ones-complements of the substitution values. The substitution block, responsive to a request to read a specified one of the substitution values, concurrently reads and outputs the specified substitution value and the corresponding ones-complement value. A power consumed in reading the specified substitution value is uniform with a power consumed in reading another one of the substitution values. The cryptographic circuit and the balancing circuit are configured to concurrently operate on each substitution value and the corresponding ones-complement value read from the memory, respectively.