Charge level display method and apparatus for a battery of an electronic device

#Cross reference is made to copending U.S. patent application Ser. No. 08/056,081 (Attorney Docket No. 5476), filed May 3, 1993, and entitled "Method and Apparatus for Displaying a Charge Level of a Battery," which is assigned to the same assignee as the present invention.

#The present invention relates to a method and apparatus for displaying charge levels of a battery and, more particularly, to a method and apparatus for displaying charge levels of a battery which is connected to an electronic device to power operation of the electronic device.

#There are many previously known designs for apparatus which display charge levels of a battery. For example, U.S. Pat. No. 5,130,659 describes a battery monitor which indicates the projected time until a battery reaches a lower threshold value indicative of the energy capacity of the battery. The battery monitor includes a microprocessor which iteratively reads the value of the battery voltage. The microprocessor then determines the rate of discharge of the battery and projects the future values of the battery voltage as well as the projected time at which the battery voltage attains the threshold voltage. This projected time is then displayed on a visual indicator, such as an LCD display. U.S. Pat. No. 5,043,651 discloses an apparatus having a rechargeable battery and a battery voltage detector which detects the output voltage of the battery to produce a detection signal when the output voltage falls below a predetermined threshold level. A controller stores a battery capacity value and accumulates the discharge of the battery to produce an accumulated capacity value. The controller also calculates a difference between the stored capacity value and the accumulated capacity value. Using the difference, a display displays the remaining charge value of the battery thereon. If the difference exceeds a predetermined value at a time the controller receives the detection signal, the controller changes the stored capacity value to a new capacity value. In addition, U.S. Pat. Nos. 3,940,679; 4,755,733; 4,827,220; 5,027,294; 5,105,180; 5,107,196; 5,124,627; 5,130,658; and 5,159,258 relate to other devices for displaying indicia of characteristics of a battery.

#FIG. 1 is a perspective view of a portable computer incorporating the features of the present invention therein, with the portable computer shown in an open condition, and with an indicator shown as being visible to a user when the portable computer is in the open condition;

#FIG. 2 is a perspective view of the portable computer of FIG. 1, with the portable computer shown in a closed condition, and with the indicator shown as being visible to a user when the portable computer is in the closed condition;

#FIG. 3 is a block diagrammatic view of the portable computer of FIG. 1;

#While the invention is susceptible to various modifications and alternative forms, a specific embodiment thereof has been shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that it is not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.

#Referring now to FIGS. 1 and 2, there is shown a portable computer, generally indicated by the reference number 10, which incorporates the features of the present invention therein. The portable computer 10 has a clam shell-like configuration. The portable computer includes a battery charge level indicator 20. In FIG. 1, the portable computer 10 is shown in an open condition in which an input device 13 (i.e. a set of input keys 13) and an output device 15 (i.e. an output display screen 15) is exposed to a user of the portable computer. As shown in FIG. 1, the indicator 20 is visible to the user when the portable computer is positioned in the open condition. In FIG. 2, the portable computer 10 is shown positioned in a closed condition in which the set of input keys 13 and the output display screen 15 is protectively stowed within the housing of the portable computer. As shown in FIG. 2, the indicator 20 is also visible to the user when the portable computer is in the closed condition. FIG. 3 shows a block diagram of the portable computer 10. The portable computer 10 further includes an electrical system 12, a battery pack 16 and a loudspeaker 22. The electrical system 12 includes a microprocessor 14. The battery pack 16 includes a Nickel Cadmium type battery or a Nickel Metal Hydride type battery. The battery pack 16 is coupled via lines 18 to the microprocessor 14. The battery pack 16 includes a number of batteries plus circuitry which electrically communicates with the microprocessor 14. For example, the battery pack circuitry allows the microprocessor 14 to periodically poll the battery pack 16 in order to determine information regarding the charge level of the batteries contained in the battery pack. The indicator 20 is coupled via line 24 to the microprocessor 14 and interprets signals from the microprocessor so as to display information regarding the charge level of the batteries contained in the battery pack 16. Also, the loudspeaker 22 is coupled to the microprocessor 14 via line 26 and is activated so as to beep at predetermined times thereby indicating certain information regarding the charge level of the batteries contained in the battery pack.

#The indicator 20 is shown in more detail in FIG. 4. In particular, the indicator 20 includes four LCD display segments 28, 30, 32 and 34 each which may be activated to display an image. When display segments 28, 30, 32 and 34 are simultaneously activated, a two dimensional image of a battery is created on the indicator 20.