A solid-state image sensor device and a differential interface thereof that are capable of ensuring stable transmission of image data while reducing power consumption. In an aspect of the present invention, a solid-state image sensor device comprises an image sensor section for outputting analog signals of an image being taken; a plurality of AD converter sections, arranged with respect to the column direction of the image sensor section, for converting the analog signals into digital signals; a drive circuit section for controlling the image sensor section and the AD converter sections; and a plurality of differential interface sections for transmitting the digital signals converted by the AD converter sections as differential output signals to an external device. Further, each of the differential interface sections comprises a current value changeover circuit for selecting a constant current to be applied in each differential interface section in accordance with each of a plurality of operation modes, and an offset voltage holding circuit for maintaining a constant offset voltage level for the differential output signals even when an operation mode changeover is made.