Switched mode power supply output stage configuration

Abstract

A method of optimizing the number of output stages of a switched mode power supply features a dynamically-updated lookup table (LUT) storing historic output stage configuration data per system operating performance point (OPP). Upon entering an OPP, a margin is added to the historic optimal configuration. During operation at the OPP, the current drawn by the load is periodically monitored, and the number of output stages is dynamically adjusted, as needed (with low pass filtering to ensure stability). When the system exits the OPP, a running average of the optimal number of output stages for the OPP is updated with the actual number of output stages enabled in this iteration of the OPP. A running average of the deviation, or change in number of output stages enabled, is also maintained. The updated values are written to the LUT, for use in setting the initial output stage configuration the next time the same OPP is invoked. This methodology is adaptive and self-learning, and automatically accounts for variations such as temperature, aging, process variation, software changes, and the like.