The present invention provides an amplifier circuit comprising a differential amplifier and a negative feedback loop circuit, in which a positive feedback loop circuit having a gain smaller than a gain of the negative feedback loop circuit is formed inside the negative feedback loop circuit. A processing core comprises a hardware transactional memory system configured to receive an early release indication for a specified word of a group of words in a read set of an active transaction. A remote control device may further be used to remotely control the motor. The controller adjusts the amount of the current flowing in the variable current source not to exceed the absolute maximum current for the APD. Any such firmware updates are recorded in a log that is accessible to system management applications. An actuating element enables the spoiler lip to be shifted between an extended operating position, in which the spoiler lip forms a downwardly directed extension of the front part and acts as an aerodynamic air-guiding device, and a retracted inoperative position, in which the spoiler lip is directed to the rear and essentially has no aerodynamic air-guiding effect.