A circuit for receiving digital signals over a transmission line. A feedback circuit is coupled to an input node of the transmission line and adjusts the input impedance of the receiver circuit to match the characteristic impedance of the transmission line. The feedback circuit includes a first current source controlled by a first voltage and having a first transconductance, and a second current source controlled by the first voltage and having a second transconductance equal to the first transconductance times a first scaling factor. The feedback circuit includes a first resistance element having a resistance equal to the first scaling factor plus one, times the characteristic impedance of the transmission line, and is coupled between the outputs of the first and second current sources. Finally, the feedback circuit also includes a differential amplifier that compares the output of the first current source to a reference value then generates the first voltage output to control each of the first and second current sources.