An inverter-type high speed driver circuit having a first inverter branch and a second inverter branch wherein each of the inverter branches comprising a parallel circuit of a serial connection of a first impedance tuning unit and a respective first clocking transistor and a serial connection of a second impedance tuning unit and a respective second clocking transistor. The impedance tuning units are configured to adapt the conductivity of the respective inverter branch to set the output impedance of the driver circuit and each of the impedance tuning units is controlled in accordance with a data stream.