Bipolar power supply voltage controlling device for driving output stage, has switching power stage controlled based on control quantity obtained from output stage, and regulating device controlling negative and positive supply voltages

摘要

The device has a switching power stage (250) for generating negative and positive supply voltages (-UV, +UV) to drive an output stage (400). A regulating device (120) controls the supply voltages during operation according to a required voltage of an output (500) of the output stage. The switching power stage is controlled based on control quantity obtained from the output stage. The regulating device regulates a step-down converter and a single-ended primary-inductor converter (SEPIC) converter. A current limiting device detects overload on an output side of the output stage.