GB2325821A

GB2325821A - Power Saving Arrangement for a Radio Receiver Having a Display

Info

Publication number: GB2325821A
Application number: GB9808862A
Authority: GB
Inventors: Osamu Yamashita
Original assignee: NEC Corp
Current assignee: NEC Corp
Priority date: 1997-04-25
Filing date: 1998-04-24
Publication date: 1998-12-02
Anticipated expiration: 2018-04-24
Also published as: GB9808862D0; AU6360898A; AU735496B2; GB2325821B; JPH10304031A

Abstract

A portable radio communication apparatus includes a timer for counting a preselected period of time since the turn-on of a power switch. On the elapse of the preselected period of time, the apparatus automatically sets up a power saving mode in which the apparatus repeatedly turns on and turns off its display at preselected intervals. In this configuration, the display is automatically turned on and turned off while the apparatus is in its waiting state, thereby saving power while displaying necessary information for the user of the apparatus intermittently.

Description

PORTABLE RADIO COMMUNICATION APPARATUS BACKGROUND OFTIE INVEN71[0N Field of the Invention The present invention relates to a portable radio communication apparatus and, more particularly, to a portable radio communication apparatus including a display.

Description of the Related Art A portable radio telephone, for example, is usually powered by a battery or a rechargeable battery because it cannot be connected to an AC power source. The problem with the battery, whether it be rechargeable or not, is that it limits the operating time of the telephone. To use the battery over a longer period of time, it is a common practice with the telephone to turn off a transmitting section included in the telephone or to cause it to operate intermittently.

On the other hand, a portable radio telephone including an LCD (Liquid Crystal Display) has a drawback that although its transmitting section and receiving section may be disconnected from a power source, the LCD consumes current if connected to the power source and reduces the operating time of the telephone.

Japanese Patent Laid-Open Publication No. 5-102910, for example, teaches a radio telephone with a power saving feature for reducing the power consumption of an LCD driver and an LCD controller for controlling it. Specifically, the radio telephone taught in this document interrupts power supply to its LCD driver when a call incoming or a key input does not occur over a preselected period of time. Further, when a call incoming or a key input does not occur on the elapse of another preselected period of time since the interruption of power supply to the LCD driver, the telephone interrupts power supply to its LCD controller.

On the occurrence of a call incoming or a key input, the telephone resumes power supply to the LCD driver and LCD controller. Such control over the LCD driver and LCD controller is assigned to a CPU (Central Processing unit) included in the telephone.

However, the radio telephone having the above configuration brings about other problems, as follows. Once the power supply to the LCD driver or the LCD controller is shut off, the LCD does not operate at all unless a call incoming or a key input occurs. Therefore, when a long period of time expires since the interruption of power supply, the user of the telephone cannot determine whether or not the telephone is operating on the basis of the appearance of the telephone. Moreover, the user cannot see information expected to appear on the LCD and representative of the charge condition of a battery and the electric field strength of a signal received from a base station. This prevents the use from determining the operating conditions of the telephone. In addition, because the CPU must control not only the telephone but also the power supply to the LCD, control assigned to the CPU is sophisticated and increases the load on the CPU.

SUMMARY OF THE INVENTION It is therefore an object of at least the preferred rrbodlments of the present invention to provide an improved portable rio camonloation apparatus capable of allavlng the user to see its operate conditions, as well as other information, even in a power saving nsde.

In accordance with the present invention, in a portable radio communication apparatus including a display and capable of holding communication by radio, power supply to the display is interrupted when a call incoming or a key input does not occur until a first preselected period of time expires since a turn-on of a power switch, and the power supply is repeatedly set up and interrupted at intervals of a second preselected period of time after the interruption of the power supply.

Also, in accordance with the present invention, a portable radio communication apparatus includes an operation section for allowing keys to be operated. A display displays information in accordance with the operation of the keys and a call incoming under the control of a display controller. A timer counts a preselected period of time and is reset by the output signal of the display controller. A power source feeds power to the display. A switch is controlled by the output of the timer for repeatedly setting up and interrupting power supply from the power source to the display.

Further, in accordance with the present invention, a method of supplying power to a display included in a portable radio communication apparatus capable of holding communication by radio has the steps of interrupting power supply to the display when a first preselected period of time elapses without any call incoming or key input since the turn-on of a power switch, and repeatedly setting up and interrupting the power supply to the display at intervals of a second preselected period of time after the interruption of the power supply.

BRIEF DESCRIPTION OF THE DRAWINGS These and other objects, features and advantages of the present invention will become more fully apparent from the following detailed description taken with the accompanying drawings in which: Fig. 1 is a block diagram schematically showing a portable radio communication apparatus embodying the present invention; Fig. 2 is a flowchait demonstrating a specific operation of the illustrative embodiment; Fig. 3 is a block diagram showing an alternative embodiment of the present invention; and Figs. 4A-4C each shows switching means included in the embodiment of Fig. 1 in a particular condition.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to Fig. 1 of the drawings, a portable radio communication apparatus embodying the present invention is shown.

While the communication apparatus is implemented as a portable telephone in the illustrative embodiment, it may alternatively be implemented as a telephone belonging to a personal handy phone system (PHS), a cordless telephone or a pager, if desired.

As shown in FIG. 1, the portable telephone includes an antenna 1 and a transmitter/receiver 2. The transmitter/receiver 2 receives a radio signal via the antenna 1 and amplifies it for frequency conversion. A baseband processing 3 executes baseband processing with the amplified signal output from the transmitter/receiver 2. A CPU 4 controls various sections constituting the telephone. A signal to be sent and processed by the baseband processing 3 is fed to the antenna via the transmitter/receiver 2 and radiated therefrom. Fig. 1 does not show any of a microphone, a speaker and an LED (Light Emitting Diddle) for an alert because they are not directly relevant to the understanding of the present invention.

An LCD controller 5 causes information to appear on an LCD 8 in accordance with the operation of keys 6. Also, the LCD controller 5 causes a call incoming, a received message, the receipt condition of the antenna 1 and so forth to selectively appear on the LCD 8 in response to a command output from the CPU 4. An LCD driver 7 feeds a drive signal to the LCD 8 under the control of the LCD controller 5.

A power source controller 9 delivers a voltage output from a power source 10 to the various sections in accordance with a power source control signal output from the CPU 4. The power source 10 should preferably be implemented by a rechargeable battery removably mounted to the telephone.

A timer 11 receives the voltage of the power source 10 via the power source controller 9 and is reset by a signal output from the LCD controller 5. Further, the timer 11 feeds switching control signals to switches 12 and 13 constituting switching means in combination. The LCD driver 7 receives the voltage output from the power source 10 via the power source controller 9 and switches 12 and 13, as will be described specifically later. Preferably, the switch 13 should be a three-point switch having two inputs and one output.

As stated above, the illustrative embodiment includes the timer 11 and switches 12 and 13, or switching means, for controlling the LCD driver 7 by using the output signal of the LCD controller 5. It is therefore possible to control the power supply to the LCD driver 7 only if the timer 11 and switching means 12 and 13 are added to a conventional portable telephone.

A specific operation of the illustrative embodiment will be described with reference to Fig. 2. As shown, when a power switch, not shown, provided on the telephone is turned on (step S101), the power source controller 106 starts feeding the output voltage of the power source 10. Then, the telephone registers its location at a base station and enters into a waiting mode. At this instant, the output voltage of the power source 10 is applied to the LCD driver 7 via the switches 12 and 13.

Specifically, the switch 12 is held in its closed position while a first terminal included in the switch 13 and connected to the output terminal of the switch 12 is held in connection with the output terminal of the switch 13. In this condition, the LCD 8 remains in its ON state (step S115).

In response to the turn-on of the power switch, the timer 11 starts counting time (step S102). Then, the CPU 4 references the output of the LCD controller 5 in order to determine whether or not conversation is under way, whether or not a call has been received, whether or not any one of the keys 6 is pressed, and so forth (steps S103-S105). Assume that conversation is under way on the telephone. Then, information representative ofthe conversation appears on the LCD 8, so that the CPU 4 feeds a signal representative of the conversation to the LCD controller 5. In response, the LCD controller S delivers a control signal assigned to conversation display to the LCD driver 7. This control signal output from the LCD controller 5 resets the timer or counter 11. A call incoming is also displayed on the LCD 8; the timer 11 monitors a control signal output from the LCD controller 5. Further, the operation of any one of the keys 6 is displayed on the LCD 8; the timer or counter 11 is reset by the output signal of the LCD controller 5.

The timer 11 started counting time counts a first preselected period of time T, preferably S minutes. On the elapse of the first period of time T (YES, step S106), the timer 11 causes the switch 12 to open. As a result, the power supply to the LCD driver 7 is interrupted, so that the LCD 8 is brought into its OFF state (step S109). Preferably, whether or not a call has been received (step S107) and whether or not any key 6 has been operated (step S 108) should be determined again on the elapse of the period of time T.

Even after opening the switch 12, as stated above, the timer 11 continuously counts time until a second period of time 2T expires (step Ski 12). When a call is received or any key 6 is pressed before the second period of time 2T expires (YES step S 1 10 or Sill), the timer 11 selects a second input terminal included in the switch 13. As a result, the output voltage of the power source 10 is fed to the LCD driver 7 via the switch 13.

On the elapse of the period of time 2T, the timer 11 closes the switch 12 in order to feed the voltage to the LCD driver 7 and thereby turns on the LCD 8 (step S113). At the same time, the timer or counter 11 is reset.

Of course, the timer 11 capable of counting the period of time 2T may be replaced with a timer capable of counting only the period of time T, in which case whether or not to feed the voltage will be determined at intervals of T. This alternative configuration is practicable with a single switch. Specifically, as shown in Fig. 3, when a timer 14 turns on or turns off a switch 15 at every interval T, the power supply to the LCD controller 7 can be controlled. In Fig. 3, the same structural elements as the elements shown in Fig. 1 are designated by identical reference numerals and will not be described specifically in order to avoid redundancy.

Further, the embodiment shown in Fig. 1 uses the two different periods of time T and 2T. In another alternative arrangement, on the elapse of the period of time T (preferably 5 minutes), the switch 12 is opened to set up a power saving mode. Thereafter, the switch 13 is operated at intervals of Tl (preferably 1 minute). It is to be noted that such an arrangement would sophisticate the circuitry if implemented by a single switch.

Figs. 4A-4C each shows a particular condition of the switches 12 and 13. As shown in Fig. 4A, when the power switch is turned on, the switch 12 is closed while the first input terminal of the switch 13 connected to the output of the switch 12 is connected to the output tenninal. Fig. 4B shows a first condition to occur at the interval of T1 after the period of time T has expired. As shown, the switch 12 is opened and prevents the output voltage ofthe power source 10 from being fed via the switching means. Fig. 4C shows a second condition to occur at the interval of T1 after the period of time T has expired. As shown, the second input terminal of the switch 13 is connected to the output tenninal, so that the output voltage of the power source 10 is fed via the switch 13.

As stated above, the telephone is selectively held in its usual mode or in the power saving mode by the operation of the switch 12. The other switch 13 selectively feeds the output voltage of the power source 10 after the power saving mode as been set up.

The above operation can be implemented by the following procedure. In the flowchart of Fig. 2, the timer or counter 11 is reset and the switch 12 is operated on the elapse of the period of time T (YES, step S106). Then, on the elapse ofthe period of time T1 short ofthe period of time T, the switch 13 is operated. On the elapse of the period of time T (YES, step S112), the timer 11 is reset and started again. Alternatively, the timer 11 may included two counters, one responsive to the period of time T and the other responsive to the period of time T1. In such a case, on the elapse ofthe period oftime T counted by one timer, the switch 13 will be controlled by the other timer. Subsequently, the two counters will be reset in the event of a call incoming or a key input.

The times to be set by the timers should preferably be variable by the user of the telephone on the keys 6.

In summary, it will be seen that the present invention provides a portable radio communication apparatus capable of turning on its display at preselected intervals even after turning it off for a power saving purpose. This allows the user of the apparatus to see whether or not the telephone is operating. In addition, the apparatus of the invention is capable of controlling power supply in accordance with the output signal of an LCD controller. Therefore, a power saving feature and control over the power supply to the display are achievable at the same time with a load on simple circuitry.

While the invention has been described with reference to specific embodiments thereof, it will be appreciated by those skilled in the art that numerous various, modifications and embodiments are possible, and accordingly, all such variations, modifications and embodiments are to be regarded as being within the spirit and scope of the invention.

Each feature disclosed in this specification (which term includes the claims) and/or shown in the drawings may be incorporated in the invention independently of other disclosed and/or illustrated features.

The description of the invention with reference to the drawings is by way of example only.

The text of the abstract filed herewith is repeated here as part of the specification.

A portable radio communication apparatus of the present invention includes a timer for counting a preselected period of time since the turn-on of a power switch providing on the apparatus. On the elapse of the preselected period of time, the apparatus automatically sets up a power saving mode. In the power saving mode, the apparatus repeatedly turns on and turns off its display at preselected intervals. In this configuration, the display is automatically turned on and turned off while the apparatus is in its waiting state, thereby saving power while displaying necessary information for the user of the apparatus intermittently.

Claims

1. A portable radio communication apparatus including a display in which a power supply to said display is interrupted when no incoming call and no key input occurs during a first preselected period of time following supply of power, and the power to the display is repeatedly supplied and interrupted at intervals of a second preselected period of time after an interruption of the power supply.

2. An apparatus as claimed in claim 1, comprising timer means for counting said first period of time and said second period of time, and switching means controlled by an output of said timer means for selectively setting up or interrupting the power supply to said display.

3. An apparatus as claimed in claim 2, wherein said switching means comprises a first switch and a second switch, said first switch being controlled during said first period of time, said second switch being controlled at the intervals of said second period of time on the elapse of said first period of time.

4. An apparatus as claimed in claim 3, further comprising means for controlling said display, said timer means being reset in response to an output signal of said control means.

5. A portable radio communication apparatus comprising: operation means permitting keys to be operated; display means for displaying information in accordance with an operation of said keys and an incoming call; display control means for controlling said display means; timer means for counting a preselected period of time and reset by an output signal of said display control means; power source means for feeding power to said display means; and switching means controlled by an output of said timer means for repeatedly setting up and interrupting power supply from said power source means to said display means.

6. An apparatus as claimed in claim 5, wherein said switching means comprises an open/close switch connected to said power source means and a change-over switch connected to said display control means, said open/close switch being controlled on the basis of whether or not said preselected period of time elapses, said change-over switch being operated when the power supply is repeatedly set up and interrupted on the elapse of said preselected period of time.

7. An apparatus as claimed in claim 6, wherein said open/close switch sets a power saving mode while said change-over switch sets up and interrupts the power supply in the power saving mode.

8. An apparatus as claimed in claim 5, wherein said preselected period of time is set on said operation means.

9. An apparatus as claimed in claim l, comprising a timer for counting said first period of time and said second period of time, and a switch controlled by an output of said timer for setting up and interrupting power supply to said display.

10. An apparatus as claimed in claim 9, wherein said switch comprises a first switch and a second switch, said first switch being controlled during an interval between the turn-on of said power switch and an elapse of said first period of time, said second switch being controlled at the intervals of said second period of time on the elapse of said first period of time.

11. An apparatus as claimed in claim 10, further comprising control means for controlling said display, said timer means being reset in response to an output signal of said control means.

12. A portable radio communication apparatus comprising: an operation section permitting keys to be operated; a display for displaying information in accordance with an operation of said keys and an incoming call; a display controller for controlling said display; a timer for counting a preselected period of time and reset by an output signal of said display controller; a power source for feeding power to said display; and a switch controlled by an output of said timer for repeatedly setting up and interrupting power supply from said power source to said display.

13. An apparatus as claimed in claim 12, wherein said switch comprises an open/close switch connected to said power source and a change-over switch connected to said display control, said open/close switch being controlled on the basis of whether or not said preselected period of time elapses, said change-over switch being operated when the power supply is repeatedly set up and interrupted on the elapse of said preselected period of time.

14. An apparatus as claimed in claim 13, wherein said open/close switch sets a power saving mode while said change-over switch sets up and interrupts the power supply in the power saving mode.

15. An apparatus as claimed in claim 12, wherein said preselected period of time is set on said operation section.

16. A method of supplying power to a display included in a portable radio communication apparatus capable of holding communication by radio, said method comprising the steps of: interrupting power supply to said display when a first preselected period of time elapses without any incoming call or key input since power was supplied; and repeatedly setting up and interrupting the power supply to said display at intervals of a second preselected period of time after an interruption of the power supply.

17. Apparatus or a method substantially as herein described with reference to or as shown in any of the accompanying drawings.