INFORMATION TERMINAL DEVICE AND OPTION UNIT THEREFOR

摘要

According to one embodiment, there is provided an information terminal device which receives power via a communication cable from a power sourcing device recognizes a class identifying power-sourcing characteristics on the basis of response characteristics to a defined value voltage given in authentication and which is configured to connect an option unit. The information terminal device comprises a resistor unit which is disposed on a power sourcing line from the communication cable and configured to vary a resistor value, a control unit which recognizes a class of the information terminal device itself and sets a resistor value in order to achieve response characteristics corresponding to the recognized class, and a storing unit which stores the set resistor value.