Multi-phase switching converter with phase shedding

摘要

A multi-phase switched-mode converter has a control circuit configured to receive a shed threshold signal indicating that the total output current has fallen below a total current threshold level. The control circuit further includes slave phase shedding switches that have a common switching pole connected to a current share amplifier of each slave power stage, a first select pole is connected to a phase target current level, and a second select pole is connected to a phase zero target current level. A control terminal is connects the phase zero target current signal to each slave power stage to decreases their output currents to approximately a zero level. When the output current approaches the zero level, the slave power stages are deactivated. A panic circuit activates the slave power stages when the load current increases precipitously.

主权项

1. A multi-phase switched-mode converter circuit configured for dropping or shedding and adding phases to dynamically maintain an operating load while continuing to provide efficient operation and avoid any transient changes to an output voltage multi-phase switched-mode converter circuit, the multi-phase switched-mode converter circuit comprising:
a control circuit configured to adjust operational signals of a master power stage and a plurality of slave power stages of the multi-phase switched-mode converter circuit, the control circuit comprising:
a phase shedding control circuit configured to receive a shed threshold signal from a phase threshold comparator indicating that a total output current magnitude has fallen below a total current magnitude threshold level such that the multi-phase switched-mode power converter circuit is no longer operating efficiently and configured to generate a plurality of phase shedding signals and a plurality of slave phase target signals, wherein each of the plurality of phase shedding signal is transferred to one of the plurality of slave power stages; anda plurality of phase control and feedback sections where in a master phase control and feedback section is connected to the master power stage and each remaining phase control and feedback section is connected to one of the plurality of slave power stages, wherein each of the plurality of phase control and feedback sections comprises:
a slave phase shedding switch comprising:
a common switching pole in communication with a current share amplifier of one of the slave power stages,a first select pole connected to receive a phase target current level from a phase current sense circuit within the master power phase,a second select pole connected to receive a phase zero target current level from a target current voltage source, anda control terminal connected to receive one of the slave phase target signals from the phase shedding control circuit such that the slave phase shedding switch transfers a connection between the first pole and the common pole when the plurality of slave power stages are operating to a connection between the second pole and the common pole to apply the phase zero target current level to a current sense amplifier within each phase control and feedback section to bring an output current of each of the plurality of slave power stages to approximately a zero level.