Patent ID: 8479032

Claim:
A data-storage device comprising: a memory control circuit; a solid-state non volatile memory circuit for providing, under control of the memory control circuit, storage of data; a volatile memory circuit having a primary-operating power and for storing, under control of the memory control circuit, write data destined for the solid-state nonvolatile memory circuit; power circuitry for receiving electrical power from an external host-system power source and for providing the received electrical power for use as the primary-operating power; and a backup power circuit including an energy-storage circuit with one or more energy storage components designed to hold sufficient energy to provide substantially all of the primary-operating power during a minimum time period sufficient to permit data transfer, of at least dirty write data, from the volatile memory circuit to the nonvolatile memory circuit, and an isolation-regulation circuit for providing voltage regulation of the electrical power received from the host-system power source, for providing the regulated voltage for charging of the energy storage circuit, and for isolating the host-system power source from the energy storage components in response to the power received from host-system power source dropping below a voltage threshold level.