Patent ID: 8320471
Filing Date: 2012-11-27
Classification: H04L

Abstract:
1. A transmission device for differential communication, comprising: a first communication line and a second communication line; a cathode-side power supply line coupled to a cathode side of a direct current power source; an anode-side power supply line coupled to an anode side of the direct current power source; a first cathode-side element part coupled between the first communication line and the cathode-side power supply line; a second cathode-side element part coupled between the second communication line and the cathode-side power supply line; a first anode-side element part coupled between the first communication line and the anode-side power supply line; a second anode-side element part coupled between the second communication line and the anode-side power supply line; a driving portion applying a differential voltage between the first communication line and the second communication line by driving one of a group of the first cathode-side element part and the second anode-side element part and a group of the second cathode-side element part and the first anode-side element part based on a value of transmission data input from an outside, and thereby transmitting the transmission data by a differential transmission method; and a target potential generating portion generating at least one of a group of a first target potential and a second target potential and a group of a third target potential and a fourth target potential, the first target potential being higher than a potential of the first communication line by a constant voltage, the second target potential being higher than a potential of the second communication line by the constant voltage, the third target potential being lower than the potential of the first communication line by the constant voltage, the fourth target potential being lower than the potential of the second communication line by the constant voltage, wherein: when the driving portion drives the first cathode-side element part and the second anode-side element part, the driving portion generates the differential voltage between the first communication line and the second communication line based on the constant voltage by at least one of inputting the second target potential to a control terminal of the first cathode-side element part and inputting the third target potential to a control terminal of the second anode-side element part; when the driving portion drives the second cathode-side element part and the first anode-side element part, the driving portion generates the differential voltage between the first communication line and the second communication line based on the constant voltage by at least one of inputting the first target potential to a control terminal of the second cathode-side element part and inputting the fourth target potential to a control terminal of the first anode-side element part; and the differential voltage generated when the driving portion drives the first cathode-side element part and the second anode-side element part and the differential voltage generated when the driving portion drives the second cathode-side element part and the first anode-side element part have different polarities.