In a line driver an input current (IINN) feeds a node (K1) which is connected to an input on an amplifier (OTA1). A further input on the amplifier (OTA1) has a reference voltage (VSGND) applied to it. The amplifier (OTA1) controls a current source (MN1) which outputs an output current (IOUTN). A current/voltage converter (R1) is connected between the node (K1) and the current source (MN1). A voltage/current converter (R2) is connected between the current source (MN1) and a ground (VSS).