A transmission buffer of a signal transmission device according to the embodiment includes: a differential circuit portion that is connected between the first potential and the second potential; a variable current source portion that supplies current to the differential circuit portion; a switch port that switches between a conductive state and a disconnected state between the first transmission terminal and the fixed potential and between the second transmission terminal and the fixed potential; and a controller that controls the current supplied by the variable current source portion to the differential circuit portion, and that controls the operation of the switch portion.

A transmission buffer of a signal transmission device according to the embodiment includes: a differential circuit portion that is connected between the first potential and the second potential; a variable current source portion that supplies current to the differential circuit portion; a switch port that switches between a conductive state and a disconnected state between the first transmission terminal and the fixed potential and between the second transmission terminal and the fixed potential; and a controller that controls the current supplied by the variable current source portion to the differential circuit portion, and that controls the operation of the switch portion.

A transmission buffer of a signal transmission device according to the embodiment includes: a differential circuit portion that is connected between the first potential and the second potential; a variable current source portion that supplies current to the differential circuit portion; a switch port that switches between a conductive state and a disconnected state between the first transmission terminal and the fixed potential and between the second transmission terminal and the fixed potential; and a controller that controls the current supplied by the variable current source portion to the differential circuit portion, and that controls the operation of the switch portion.

A transmission buffer of a signal transmission device according to the embodiment includes: a differential circuit portion that is connected between the first potential and the second potential; a variable current source portion that supplies current to the differential circuit portion; a switch port that switches between a conductive state and a disconnected state between the first transmission terminal and the fixed potential and between the second transmission terminal and the fixed potential; and a controller that controls the current supplied by the variable current source portion to the differential circuit portion, and that controls the operation of the switch portion.

A transmission buffer of a signal transmission device according to the embodiment includes: a differential circuit portion that is connected between the first potential and the second potential; a variable current source portion that supplies current to the differential circuit portion; a switch port that switches between a conductive state and a disconnected state between the first transmission terminal and the fixed potential and between the second transmission terminal and the fixed potential; and a controller that controls the current supplied by the variable current source portion to the differential circuit portion, and that controls the operation of the switch portion.

A transmission buffer of a signal transmission device according to the embodiment includes: a differential circuit portion that is connected between the first potential and the second potential; a variable current source portion that supplies current to the differential circuit portion; a switch port that switches between a conductive state and a disconnected state between the first transmission terminal and the fixed potential and between the second transmission terminal and the fixed potential; and a controller that controls the current supplied by the variable current source portion to the differential circuit portion, and that controls the operation of the switch portion.