Patent ID: 8619973

Claim:
An encryption device, comprising: a first exclusive-OR gate coupled to a first input data, a second exclusive-OR gate coupled to a second input data, a third exclusive-OR gate coupled to a third input data, and a fourth exclusive-OR gate coupled to a fourth input data; and a first flip-flop having a first input coupled to an output of the first exclusive-OR gate, a second flip-flop having a second input coupled to an output of the second exclusive-OR gate, a third flip-flop having a third input coupled to an output of the third exclusive-OR gate, and a fourth flip-flop having a fourth input coupled to an output of the fourth exclusive-OR gate; wherein the second exclusive-OR gate receives as input an output from the first flip-flop and an output from the fourth flip-flop, and further directly receives as another input the second input data.