Abstract: A power supply device for an electronic apparatus includes a housing, a battery unit disposed in the housing, a control circuit disposed in the housing and coupled electrically to the battery unit, and a power transmission cord having an inner end coupled to the control circuit, and an outer end that extends out of the housing and that is terminated by an electrical connector to permit electrical connection with the electronic apparatus. The control circuit is operable so as to control supply of battery power from the battery unit to the electronic apparatus via the power transmission cord. A cord spool is mounted operably in the housing, and is operable for winding and unwinding the power transmission cord thereon.

Abstract: A combined digitizer tablet and external power supply device for an electronic apparatus includes a housing, a battery unit disposed in the housing, and a sensing tablet unit disposed on the housing and that generates electrical signals in response to writing activity thereon. A control circuit is coupled electrically to the sensing tablet unit and the battery unit, and receives the electrical signals from the sensing tablet unit to generate corresponding coordinate position data. A data communications unit establishes a communications link with the electronic apparatus to transmit the coordinate position data thereto. A power output unit is coupled electrically to the control circuit, and enables electrical coupling to the electronic apparatus. The control circuit controls the supply of battery power from the battery unit to the electronic apparatus via the power output unit.