US Patent 7140546 Battery pack with integrated human interface devices

A power pack with human interface devices that includes a power pack housing, which is detachably interfaced to a portable device. The power pack includes a power source internal to the housing for providing power, a light source internal to the housing for producing a light signal associated with a status, which light signal is viewable external to the housing, and an audio source internal to the housing for producing an audio signal associated with the status. The power pack interfaces electrically to the portable device to provide power thereto, and receive therefrom control signals associated with the status, which control signals activate at least one of the light source and audio source according to the status.