Power supply with a magnetically uncoupled phase and an odd number of magnetically coupled phases, and control for a power supply with magnetically coupled and magnetically uncoupled phases

摘要

An embodiment of a power supply includes an input node operable to receive an input voltage, an output node operable to provide a regulated output voltage, an odd number of magnetically coupled phase paths each coupled between the input and output nodes, and a first magnetically uncoupled phase path coupled between the input and output nodes. Such a power supply may improve its efficiency by activating different combinations of the coupled and uncoupled phase paths depending on the load conditions. For example, the power supply may activate only an uncoupled phase path during light-load conditions, may activate only coupled phase paths during moderate-load conditions, and may activate both coupled and uncoupled phase paths during heavy-load conditions and during a step-up load transient.

主权项

1. A power supply, comprising:
an input node configured to receive an input voltage; an output node configured to provide a regulated output voltage; an odd number of magnetically coupled phase paths each coupled between the input and output nodes; a first magnetically uncoupled phase path coupled between the input and output nodes; and a power-supply controller coupled to the phase paths and configured:
to activate each of the magnetically coupled phase paths at a first frequency; andto activate the magnetically uncoupled phase path at a second frequency that is substantially equal to a product of the first frequency and the odd number.