A device and a method for determining the current position of a rotor, particularly the angle of rotation of the rotor, of an electric motor, wherein said device determines the current position of the rotor using the fluctuations of the armature current or the armature voltage of the electric motor. The fluctuations of the armature current or the armature voltage are separated from the fluctuations of the motor current or the motor voltage with the help of an amplifier unit dependent on a controllable offset value. The offset value is changed according to the motor current or the motor voltage. By virtue of the device and the method, the fluctuations of the armature current or the armature voltage can be separated from the fluctuations of the motor current or the motor voltage over the full measurement range of the motor current or the motor voltage.