Patent ID: 7932706
Filing Date: 2011-04-26
Classification: H03F

Abstract:
1. A power supply circuit comprising: a first input configured to receive an input voltage having a first value for operating the power supply circuit; a return configured to form a common terminal for the input voltage wherein the first value is referenced to a potential of the return; a first circuit configured to receive the input voltage and form a first voltage having a second value that is less than the first value, the second value having a first magnitude; a second circuit configured to receive the input voltage and form a second voltage having a third value that is negative referenced to the potential of the return wherein a second magnitude of the third value is less than the first value; a first regulator circuit configured to use the potential of the return and the second voltage as an operating voltage, the regulator circuit configured to receive the first voltage and form a third voltage that is negative referenced to the potential of the return and having a third magnitude that is substantially equal to the first magnitude; and a first audio amplifier configured to receive the first voltage as a positive operating voltage and the third voltage as a negative operating voltage.