Disclosed is a method of operating a system-on-chip automatic design device. The system-on-chip automatic design device includes a first synthesizer and a second synthesizer. The method includes generating a first code, based on information of a first signal and information of a second signal that are used in a first IP (Intellectual Property) block, classifying a first signal code corresponding to the first signal and a second signal code corresponding to the second signal from the first code, synthesizing, through the first synthesizer, a first communication architecture configured to transmit the first signal, based on the classified first signal code, and synthesizing, through the second synthesizer, a second communication architecture configured to transmit the second signal based on the classified second signal code.