Rotationally-molded outdoor furniture takes up little space when unassembled, but is easily assembled and durable requiring only one fastener to support the weight of an adult. The neutral point shift section shifts a neutral point of phase voltage commands so that the values of the phase voltage commands after the shifting of the neutral point come within the amplitude of a triangular wave, and inputs the phase voltage commands with the neutral point having been shifted, to a control signal output section. Various polysilicon microphone structures are formed above a front side of the top silicon layer by depositing at least one oxide layer, forming the structures, and then removing a portion of the oxide underlying the structures from a back side of the top silicon layer through trenches formed through the top silicon layer. The output of the DSP maybe routed by the network processor to physical layer devices.