Patent ID: 8310276

Claim:
A differential transmission circuit comprising: a sending unit that generates a pair of differential signals from an input signal, and sends the differential signals; a receiver that receives the differential signals sent by the sending unit; and a transmission path that transmits the differential signals from the sending unit to the receiver, wherein the sending unit has a selector that selects one of the input signal and a signal obtained by inverting a polarity of the input signal so as to ensure a compatibility of a circuit arrangement on a board, and generates the differential signals from the signal selected by the selector, wherein the transmission path includes a first transmission path that transmits first differential signals from the sending unit to the receiver, and a second transmission path that transmits second differential signals from the sending unit to the receiver, wherein the input signal includes a first input signal and a second input signal, wherein the selector has: a first selector that selects one of the first input signal and a signal obtained by inverting a polarity of the first input signal; a second selector that selects one of the second input signal and a signal obtained by inverting a polarity of the second input signal; a third selector that selects, as a third signal, one of the signal selected by the first selector and the signal selected by the second selector; and a fourth selector that selects, as a fourth signal, one of the signal selected by the first selector and the signal selected by the second selector, and wherein the sending unit generates the differential signals from each of the third signal and the fourth signal.