To provide a communication controller in which an A/D converter section is used in common and a trouble of adding an A/D converter is omitted in the case of increasing analog sensors.

The communication controller has input output lines that interconnect an input output unit 2 and a central control unit 3 for data transmission, a central control unit 3 that makes calculation for load control based on data from the input output lines and has an A/D converter section 32, and the input output unit 2 to which a switch 4 and sensors 8, 9 are connected to its input side and to which a load such as a motor 5 is connected to its output side. In this case, the input output lines are digital transmission lines B1, B2 and an analog data transmission line A1 and the input output unit 2 sends data denoting an analog data channel through the digital data transmission line B1 in the case of sending the analog data.