ARRANGEMENT AND METHOD FOR PROVIDING POWER TO A CIRCUIT USING SWITCHED CAPACITOR TECHNIQUES

Switching power supplies are implemented using a variety of methods and devices. According to an example embodiment of the present invention, an arrangement provides power to a circuit by selecting between a first supply and a second supply. The arrangement includes a first circuit that charges a first capacitive element using the first supply and generates a first reference voltage by distributing charge between the first capacitive element and a second capacitive element. The arrangement also includes a first comparator that compares the first reference voltage to a second reference voltage derived from the second supply and a second comparator that compares the first reference voltage to a third reference voltage. The arrangement further includes a power control circuit that selects one of the supplies based on the results of the comparisons.