The invention relates to an operating state circuit for driving an inverter with half-bridges having respective switching devices, which inverter supplies an n-phase supply voltage to an n-phase electrical machine via phase connections associated with the respective half-bridges, where n\u22671. An embodiment of the method for producing a semiconductor layer includes: forming a film containing a metal element and an oxygen element; generating oxygen gas by heating the film; and forming a semiconductor layer containing a metal chalcogenide from the film by allowing the metal element to react with a chalcogen element. The amplifier circuit 20 has a driving section including a PMOS transistor T1 and an NMOS transistor T2, the respective drain terminals thereof being connected to each other. A shielding gasket is disposed around the shielding shell and has overlapping rows of beams extending therefrom. The method further comprising performing a rounding operation of the signal by the rounding unit after the transformation by the auxiliary transformation matrix. A third voltage and a fourth voltages are applied to other rows and columns which are not connected to the selected organic light emitting diode to provide a reverse bias to all the remaining light emitting diodes.