A system includes a voltage converter configured to provide a first output voltage at a first output terminal, wherein the first output voltage is from a first group comprising a first high regulation voltage, a first low regulation voltage, and a battery voltage. A first plurality of circuits has power supply terminals coupled to the first output terminal. A power control circuit uses information about operational states of the plurality of circuits to direct the voltage converter to provide the first output voltage from the first group appropriate for the operational states of the first plurality of circuits.