Backup energy storage module with selectable charge storage elements for providing backup power to a load

摘要

A backup energy storage module is disclosed including a plurality of charge storage elements, each charge storage element operable to be charged to a backup voltage. The backup energy storage module further includes control circuitry operable to monitor a supply voltage that provides power to a load, determine when the supply voltage falls below a threshold level, select a first charge storage element to provide power to the load, determine when the backup voltage on the first charge storage element falls to a reference level, and select a second charge storage element to provide power to the load if the supply voltage remains below the threshold level.