A semiconductor device driving unit to supply a drive signal to a gate of a semiconductor switching device, the semiconductor device driving unit comprising: a plurality of gate impedance circuits selectably connectable to the gate of the semiconductor switching device; and a selector to select one or more of the gate impedance circuits to connect to the semiconductor switching device. Also provided is a method of supplying a drive signal to a gate of a semiconductor switching device, the method comprising: selecting one or more of a plurality of gate impedance circuits to be connected to the gate of the semiconductor switching device based on one or more operating conditions and stored data relating to the one or more operating conditions; and connecting the selected one or more of the gate impedance circuits to the semiconductor switching device.