A communication circuit includes first and second communication nodes including first and second control chips, respectively, and first and second communication chips connected to the first and second control chips, respectively. The first and second communication chips are connected to each other through first and second signal lines, and are configured to transmit a differential signal. The first communication chip includes an output port to output a level signal obtained from the differential signal to the first control chip. The communication circuit further includes a voltage division assembly connected to the first and second signal lines, and configured to cause a voltage value of the first signal line to be higher than that of the second signal line when the first and second signal lines are in idle state. The first control chip includes a detection port connected to the output port to acquire the level signal.