US Patent 9213835 Method and integrated circuit for secure encryption and decryption

In one embodiment of the present invention, a secure cryptographic circuit arrangement is provided. The secure cryptographic circuit includes a cryptographic processing block, a spreading sequence generator, and a delay control circuit. The cryptographic processing block has a plurality of signal paths. One or more of the plurality of signal paths includes respective adjustable delay circuits. The spreading sequence generator is configured to output a sequence of pseudo-random numbers. The delay control circuit has an input coupled to an output of the spreading sequence number generator and one or more outputs coupled to respective delay adjustment inputs of the adjustable delay circuits. The delay control circuit is configured to adjust the adjustable delay circuits based on the pseudo-random numbers.