JP2002228731A - Electronic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic equipment capable of displaying a residual quantity of a battery corresponding to the real residual quantity of the battery. SOLUTION: This electronic equipment 1 to be operated by a built-in battery 2 as a driving source is provided with a voltage detecting unit 3 for detecting a battery voltage V0 of the battery 2, a display 5 for digitally displaying the residual quantity of the battery 2, and a control unit 9 for specifying the residual quantity of the battery on the basis of the detected battery voltage V0 and for displaying the residual quantity of the battery in the display unit 5. The control unit 9 renews the residual quantity of the battery displayed as a specified residual quantity when the specified residual quantity of the battery is smaller than the residual quantity of the battery displayed in the display unit 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic device which operates using a built-in battery as a drive source.

[0002]

2. Description of the Related Art Generally, an electronic device (a portable electronic device such as a portable information terminal) that operates using a built-in battery as a drive source.
Is configured to be able to select and use any one of a readily available dry battery (eg, an alkaline battery) and a low-cost rechargeable battery (eg, a nickel-metal hydride battery) which can be charged and used repeatedly. In such an electronic device, the remaining battery level of the built-in battery is displayed on a display unit by a digital display such as a bar display, a numerical display, a symbol display, and a symbol display. A configuration is adopted that can prevent the device from suddenly becoming unusable or malfunctioning. In this case, in a normal electronic device, a voltage between terminals of a battery (hereinafter, also referred to as “battery voltage”) in a state where a current is supplied to a load is detected, and a threshold that is set in advance and stored in a memory. The current battery remaining amount is specified by comparing the value voltage with the detected battery voltage, and the battery remaining amount is displayed on the display unit.

[0003]

However, this conventional electronic device has the following problems. That is, in general, the battery voltage changes depending on the load on the battery even when the remaining battery level is the same. Specifically, the battery voltage decreases during a heavy load state, and returns and increases during a light load state. In an electronic device, the amount of load on a battery greatly changes in each operation mode according to each operation state of a large number of built-in circuits. On the other hand, in a conventional electronic device, the remaining battery level is specified by simply comparing the detected battery voltage with a threshold voltage defined for one type regardless of the load amount of the battery. For this reason,
When the battery voltage returns and rises due to the change in the operation mode of the electronic device and the load amount on the battery has shifted to a light load, even though the battery remaining amount has not actually increased, In some cases, for example, the display indicating that the specified remaining battery level is “low” is returned to the display indicating “the remaining level is medium”. Therefore, the conventional electronic device has a problem that the displayed remaining battery level does not match the actual remaining battery level. If the remaining battery level is displayed incorrectly, the operation of the electronic device may not be completed normally. In such a case, the destruction of data stored in the electronic device is a particular problem.

[0004] The discharge characteristics of a dry battery such as an alkaline battery are greatly different from the discharge characteristics of a rechargeable battery such as a nickel hydride battery. In particular, when the alkaline battery is fully discharged and is in a light load state, the voltage of each alkaline battery drops to 1.05 V. However, when left for a while,
In a light load state, the voltage returns to about 1.25 V per line and rises. On the other hand, the nickel-metal hydride battery drops to about 1.25 V per battery in a slightly used state, and drops to about 1.05 V in a lightly loaded state in a fully discharged state. In this case, when the alkaline battery or the nickel-metal hydride battery in the fully discharged state shifts from the light load state to the heavy load state, the voltage drops at that moment. Therefore, from the viewpoint of preventing malfunction of electronic equipment, it is necessary to eliminate the continuous use of batteries in these states, and furthermore, the threshold voltage of each battery is set to be 1. It is necessary to display a warning to prompt the user to replace the battery when the voltage is set to 25 V and falls below this threshold.
However, the battery voltage of an alkaline battery in a state where the voltage has been completely discharged and the voltage has been restored is substantially equal to the battery voltage of a nickel-metal hydride battery in a slightly used state of 1.25 V per battery. When a nickel-metal hydride battery having low characteristics is used, there is also a problem that it is difficult to fully use the battery capacity.

[0005] The present invention has been made in view of the above problems, and has as its main object to provide an electronic apparatus capable of displaying a remaining battery level that matches an actual remaining battery level.

[0006]

According to a first aspect of the present invention, there is provided an electronic apparatus which operates using a built-in battery as a drive source, wherein the voltage detecting unit detects a battery voltage of the battery. A display unit for digitally displaying the remaining battery level of the battery, and a control unit for specifying the remaining battery level based on the detected battery voltage and displaying the remaining battery level on the display unit. The control unit updates the displayed remaining battery level with the specified remaining battery level only when the specified remaining battery level is smaller than the remaining battery level displayed on the display unit. It is characterized by the following. Note that “display digitally” here includes bar display, numerical display, symbol display, and symbol display.

According to a second aspect of the present invention, in the electronic device according to the first aspect, a display remaining amount storage unit that stores the remaining battery amount displayed on the display unit and the battery remaining amount are specified. A threshold storage unit for storing a plurality of threshold voltages for comparing the detected battery voltage with each threshold voltage stored in the threshold storage unit. The temporary battery remaining amount is specified and the temporary battery remaining amount is displayed as the battery remaining amount only when the temporary battery remaining amount is smaller than the battery remaining amount stored in the display remaining amount storage unit. And displaying the updated remaining amount in the display remaining amount storage unit as the new remaining amount of the battery.

According to a third aspect of the present invention, there is provided an electronic apparatus which operates by using a built-in battery as a driving source, wherein a voltage detecting unit for detecting a battery voltage of the battery, and a load amount for detecting a load amount on the battery. A detecting section, a display section for digitally displaying the remaining battery level of the battery, and a light load section for storing a plurality of light load threshold voltages for specifying the remaining battery level in a light load state. A threshold storage unit, and a plurality of heavy load threshold voltages for specifying the remaining battery level at the time of a heavy load state, each being set to a voltage lower than the light load threshold voltage. A heavy load threshold storage unit for storing, and a control unit for specifying the remaining battery level based on the detected battery voltage and displaying the remaining battery level on the display unit, wherein the control unit includes: The detected load amount is When in the load state, each of the light load threshold voltages is compared with the detected battery voltage to identify the remaining battery level, and when the detected load amount is a heavy load, each of the heavy load thresholds is used. The battery level is specified by comparing a threshold voltage with the detected battery voltage.

According to a fourth aspect of the present invention, in the electronic device according to any one of the first to third aspects, at least the light load state, the medium load state, and the heavy load state are obtained by using the battery as a driving source. An electronic device operating in three aspects, wherein the control unit shifts the electronic device to the medium load state when shifting from the light load state to the heavy load state, and performs the detection during the medium load state. When the set battery voltage is lower than a preset threshold voltage, the shift to the heavy load state is stopped.

According to a fifth aspect of the present invention, in the electronic apparatus according to any one of the first to third aspects, the battery is roughly divided into at least a light load state, a medium load state, and a heavy load state using the battery as a driving source. An electronic device operating in three aspects, wherein the control unit shifts the electronic device to the medium load state when shifting from the light load state to the heavy load state, and performs the detection during the medium load state. The operation of the electronic device is stopped when the set battery voltage is lower than a predetermined threshold voltage set in advance.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. An example will be described in which the present invention is applied to a portable mail terminal (or a mail terminal) that transmits and receives data such as mail by connecting to a mobile phone.

First, the configuration of the electronic device 1 will be described with reference to FIG.
This will be described with reference to FIG.

As shown in FIG. 1, an electronic device 1 includes a battery 2, a voltage detector 3, an input unit 4, a monochrome LCD 5, a color L
It comprises a CD 6, a backlight 7, a memory 8, and a control unit 9, and operates using the built-in battery 2 as a drive source. In this case, the battery 2 is configured by any one of two types selected from a dry battery (for example, an alkaline dry battery) and a rechargeable battery (for example, a nickel-metal hydride battery). The voltage detection unit 3 is configured by an A / D converter as an example, and includes a battery 2
Is converted from analog to digital and output as voltage data DV. The input unit 4 includes a keyboard, a digital camera, and the like. Black and white LCD
Reference numeral 5 denotes a display unit according to the present invention, which is activated when the first control signal S1 is inputted, and mainly operates an operation menu of the electronic device 1 and a keyboard based on display data D1 outputted by the control unit 9. The characters input by the operation and the remaining battery power of the battery 2 are displayed. In this case, the black-and-white LCD 5 digitally displays the remaining battery level (for example, in a bar shape). Specifically, black and white L
When the remaining battery level is “sufficient”, the CD 5
As shown in FIG. 3, three segments are lit and displayed, and when the remaining battery power is in a “medium” state, as shown in FIG.
Two segments light up and the battery level is low
In this state, as shown in FIG. 4, one segment is lit and displayed, and when the remaining battery level is "insufficient", all segments are turned off and a warning is displayed to prompt the user to replace the battery.

The color LCD 6 is activated when the second control signal S2 is inputted, and displays an image mainly taken by a digital camera based on the display data D2 outputted by the control section 9. The backlight 7 is
A light source for the color LCD 6, and a third control signal S3
Lights when is input. The memory 8 is a ROM or a RAM
And stores an operation program of the control unit 9 and is used as a display remaining amount storage unit 10, a threshold value storage unit 11, and a work area unit. In this case, the display remaining amount storage unit 10 stores a code for specifying the remaining battery amount currently displayed on the monochrome LCD 5 (hereinafter, also referred to as “display battery remaining amount”). Stores a plurality of threshold voltages for specifying the remaining battery level. Also,
As the threshold voltage, three types of VU, VM, and VL (VU>VM> VL) are used corresponding to the above-mentioned three levels of the remaining battery level.

The control unit 9 is constituted by a CPU or the like, and operates in accordance with an operation program stored in the memory 8 to control other components of the electronic device 1 in an integrated manner. For example, the first control signal S1 is output to operate the monochrome LCD 5, and the display data D1 is output to display an operation menu and the like. Further, the control unit 9 operates the other components in accordance with the operation menu selected by operating the keyboard. For example, when the image capture menu is selected by the keyboard, the lower-level menu related to image capture is displayed on the monochrome LCD 5. Further, when an image capturing operation is selected from the lower menu, the digital camera is operated and image data is captured and stored in the memory 8. In this case, the control unit 9
Outputs the second control signal S2 to operate the color LCD 6, and at the same time reads out the image data stored in the memory 8 and outputs the display data D2, thereby displaying the captured image on the color LCD 6. . At this time, the control unit 9 outputs the third control signal S3 to turn on the backlight 7 so that the image displayed on the color LCD 6 can be viewed. Further, the control unit 9 fetches the voltage data DV output from the voltage detection unit 3 and detects the current battery voltage VO based on the voltage data DV. Further, the control unit 9 determines the detected battery voltage VO,
Each threshold voltage (V) read from the threshold storage unit 11
U, VM, and VL) to determine the temporary battery remaining amount, and further compare the temporary battery remaining amount with the display battery remaining amount read from the display remaining amount storage unit 10 to determine the temporary battery remaining amount. Only when the display battery level is smaller than the display battery level, the display battery level of the monochrome LCD 5 is updated and displayed with the provisional battery level as a new battery level. When the temporary battery remaining amount is equal to or larger than the display battery remaining amount, the control unit 9 continues to display the present display battery remaining amount without updating the battery remaining amount display of the monochrome LCD 5.

Next, the display process A of the remaining battery level by the control unit 9 will be described with reference to FIG.

First, the control unit 9 detects the battery voltage VO by taking in the voltage data DV output from the voltage detection unit 3 (step 51). Next, the control unit 9
The battery voltage VO is compared with each of the threshold voltages VU, VM, VL read from the threshold storage unit 11 to specify the provisional battery remaining amount (step 52). Specifically, the control unit 9
When VO ≧ VU, the provisional battery remaining amount is specified as a “sufficient” state, when VU> VO ≧ VM, the provisional battery remaining amount is specified as a “medium” state, and when VM> VO ≧ VL , The temporary battery remaining level is specified as “low”, and
When L> VO, the temporary battery remaining amount is specified as a state requiring a warning.

Next, the control unit 9 determines whether or not the specified temporary battery remaining amount is in a state requiring a warning (step 5).
3) If it is determined that a warning is required, a warning is displayed on the monochrome LCD 5 to prompt the user to replace the battery, and then the power supply of the electronic device 1 is forcibly shut off (step 54). On the other hand, when it is determined that the specified temporary battery remaining amount is in a state other than the state requiring a warning, the specified temporary battery remaining amount is compared with the display battery remaining amount read from the display remaining amount storage unit 10 (step 55). At this time, only when the control unit 9 determines that the temporary battery remaining amount is smaller than the display battery remaining amount (for example, when the display battery remaining amount is “medium”, the temporary battery remaining amount is “small”) Only when the determination is made, the temporary battery remaining amount is updated and displayed on the monochrome LCD 5 as the actual battery remaining amount, and the temporary battery remaining amount is updated and stored in the display remaining amount storage unit 10 as a new display battery remaining amount ( Step 5
6) Then, the process proceeds to step 51. When the temporary battery remaining amount is equal to or larger than the display battery remaining amount (for example, when the display battery remaining amount is “medium”, the temporary battery remaining amount is “medium” and “sufficient”), the step Go directly to 51. Therefore, in this case, the display battery remaining amount displayed on the monochrome LCD 5 is not updated, and the display battery remaining amount stored in the display remaining amount storage unit 10 is not updated. Is taken over as it is.

As described above, according to the electronic apparatus 1, only when it is determined that the temporary battery remaining amount is smaller than the display battery remaining amount, the temporary battery remaining amount is set as the actual battery remaining amount and the monochrome LCD 5 is used.
And the temporary battery remaining amount is updated and stored in the display remaining amount storage unit 10 as a new display battery remaining amount, so that unlike a conventional electronic device, an error caused by a change in the load amount of the battery 2 is caused. Display can be avoided, whereby the remaining battery level of the monochrome LCD 5 can be matched with the actual remaining battery level.

Next, an electronic device 21 according to a second embodiment of the present invention will be described. Note that the same components as those of the electronic device 1 are denoted by the same reference numerals, and redundant description will be omitted.

As shown in FIG. 1, the electronic equipment 21 includes a light load threshold storage part 11a and a heavy load threshold storage part 11b instead of the threshold storage part 11 in the electronic equipment 1.
And two threshold storage units. In this case, as described above, the light-load threshold storage unit 11a stores three light-load thresholds for specifying the remaining battery capacity in the light-load state, in accordance with the display battery remaining amount displayed in three stages. Value voltage V
LU, VLM, and VLL (VLU>VLM> VLL) are stored. The heavy-load threshold storage unit 11b stores three heavy-load threshold voltages VHU, VHM, and VHL (VHU>VHM> VHL) for identifying the remaining battery level in the heavy load state. . In this case, each heavy load threshold voltage VHU, VH
M and VHL are the corresponding light load threshold voltages VLU and VL
The voltage is set lower than M and VLL. That is, it is set so as to satisfy VLU> VHU, VLM> VHM, and VLL> VHL. In addition, as for the value of each threshold voltage when using an alkaline dry battery and a nickel hydrogen battery,
For example, as a voltage per two lines, a light-load threshold voltage V
LU, VLM and VLL are 2.60 volts and 2.45 volts respectively.
Volts and 2.05 volts, and heavy load threshold voltages VHU, VHM, and VHL are 2.40 volts, respectively.
It is regulated at 2.30 volts and 2.02 volts.

The controller 9 also functions as a load detector for detecting the load of the battery 2. Specifically, the electronic device 2
1 is controlled by the control unit 9, the load amount of each component is measured in advance and stored in the memory 8, so that the control unit 9 operates in the current operation mode (operation state). ) Detect the load of the battery 2 below. In addition,
A dedicated load amount detection unit is provided for detecting a current value output from the battery 2 to detect a load amount of the battery 2, and the control unit 9 controls the load of the battery 2 based on the current value detected by the load amount detection unit. A configuration in which the amount is detected and the threshold is switched may be employed.

Next, the remaining battery level display processing B by the control unit 9 of the electronic device 21 will be described with reference to FIG.

First, the control section 9 detects the current load amount on the battery 2 based on the current operation mode (ie, the type of the component currently being driven and controlled) (step 61). Next, based on the detected load amount, the threshold voltage value for battery remaining amount specification is switched (step 6).
2). In this case, for example, when the detected load amount is in a light load state (for example, when the monochrome LCD 5 is driven and the color LC
D6 and backlight 7 are not driven)
Switching to the threshold voltages VLU, VLM, VLL stored in the light load threshold storage unit 11a is performed. On the other hand, when the detected load amount is in a heavy load state (for example, when the monochrome LCD 5 is driven and the color LCD 6 and the backlight 7 are driven), the load is stored in the heavy load threshold storage unit 11b. Switch and set to threshold voltage VHU, VHM, VHL.

Next, the control unit 9 detects the battery voltage VO by taking in the voltage data DV output from the voltage detection unit 3 (step 63), and thereafter, stores the light load threshold value storage unit 11a (or the heavy load). The temporary battery remaining amount is specified by comparing each of the threshold voltages VLU, VLM, VLL (or VHU, VHM, VHL) read from the threshold storage unit 11b) with the battery voltage VO (step 64). ). Specifically, the control unit 9 determines that VO ≧ VLU (or VO ≧ VH
U), the provisional battery remaining amount is specified as “sufficient”, and if VLU> VO ≧ VLM (or VHU> VO ≧ VHM), the provisional battery remaining amount is specified as “medium”. V
When LM> VO ≧ VLL (or VHM> VO ≧ VHL), the temporary battery remaining amount is specified as “low”, and
LL> VO (or VHL> VO, in this case VLL, VHL
(Corresponding to a predetermined threshold value in the present invention), the provisional battery remaining amount is specified as a state requiring a warning. next,
The control unit 9 determines whether or not the identified temporary battery remaining amount is in a state requiring a warning (step 65). If it is determined that the state requires a warning, a warning display is displayed on the monochrome LCD 5 to prompt replacement of the battery. Is performed, the power supply of the electronic device 21 is forcibly shut off to stop the operation of the electronic device 21 (step 66). On the other hand, when it is determined that the specified temporary battery remaining amount is in a state other than the state requiring a warning, the specified temporary battery remaining amount is updated and displayed on the monochrome LCD 5 as a display battery remaining amount (step 67), and then the process proceeds to step 61. .

As described above, according to the electronic device 21,
The threshold voltage is switched between the heavy load state and the light load state according to the load amount of the battery 2 to specify the remaining battery level, so that the threshold voltage is fixed to one type regardless of the load amount of the battery 2. The remaining battery level can be more accurately specified as compared with a conventional electronic device that specifies the remaining battery level using the threshold voltage. Further, when the load amount of the battery 2 shifts from the heavy load state to the light load state, the battery voltage VO
Even if the battery voltage returns and rises, by switching to the light-load threshold voltage higher than the heavy-load threshold voltage, the temporary battery remaining capacity in the light-load state specified in step 64 becomes heavy. An erroneous display of the remaining battery level, which is higher than the remaining battery level in the load state, can be avoided, whereby a remaining battery level that matches the actual remaining battery level can be displayed.

The present invention is not limited to the above embodiments of the present invention. For example, the process of displaying the battery voltage in the electronic device 1 may incorporate the switching process of the threshold voltage according to the load of the battery, which is performed in the process B of displaying the battery voltage in the electronic device 21. Specifically, as a pre-process of the battery voltage detection process (step 51) in the battery voltage display process A (step 51), the battery load amount detection process in the battery voltage display process B (step 61)
And a threshold voltage switching process (step 62). According to this processing, by switching the threshold voltage according to the load amount of the battery 2, the remaining battery level can be accurately specified, and the black-and-white LCD 5 can be operated in spite of the fact that the remaining battery level of the battery 2 has not increased. It is possible to avoid an erroneous display of an increase according to the remaining amount of the display battery.

In the electronic devices 1 and 21 described above, the control unit 9 operates the monochrome LCD 5 and operates the color LCD.
6 and backlight 7 do not operate (light battery 2
Load current of about 50 mA)
5. When shifting to the heavy load state (the load current of the battery 2 is 300 to 400 mA) in which the color LCD 6 and the backlight 7 are operated, instead of immediately shifting from the light load state to the heavy load state, The black and white LCD 5 and the color LCD 6 may be operated, and the backlight may be temporarily shifted to a medium load state in which the backlight 7 for the color LCD 6 is not operated (the load current of the battery 2 is about 100 mA) and then to the heavy load state. in this case,
When the controller 9 determines that the battery voltage VO detected by the voltage detector 3 is lower than the threshold voltage VREF stored in the memory 8 in the middle load state, the control section 9 prohibits the shift to the heavy load state. I do.

Specifically, an outline of the operation at the time of transition from the light load state to the heavy load state will be described with reference to FIG. In this configuration, the light load state (black and white LCD 5
When the control unit 9 shifts from the black-and-white display to the mode in which the color LCD 6 is operated, the control unit 9 first temporarily shifts to a medium load state in which only the color LCD 6 is operated without operating the backlight 7 (step 72). ), The battery voltage VO detected by the voltage detector 3 during the medium load state and the threshold voltage VREF read from the memory 8 (for example, 1
Then, the battery voltage VO of the battery 2 is determined by comparing the voltage of the battery 2 (step 73). At this time, when the battery voltage VO is lower than the threshold voltage VREF, the operation of the color LCD 6 is stopped to prohibit the shift to the heavy load state (operation of color display is stopped) (step 7).
4) Display a warning on the monochrome LCD 5 that the remaining battery power is insufficient (step 75). On the other hand, when the battery voltage VO is equal to or higher than the threshold voltage VREF, the backlight 7 is turned on to shift to a heavy load state (step 76).

According to this configuration, it is possible to determine whether or not to shift to the heavy load state in the medium load state closer to the heavy load state than in the light load state. It is possible to more reliably prevent the malfunction (system down) of the electronic devices 1 and 21 caused by the drastic reduction. In addition, the battery voltage of an alkaline battery in a state where the voltage has been fully discharged and the voltage has been restored significantly decreases during a medium load state, whereas the battery voltage of a nickel hydride battery in a slightly used state slightly decreases. , While maintaining a battery voltage higher than the battery voltage of the alkaline battery that has been greatly reduced. For this reason, a fully discharged alkaline battery can prompt the user to replace it with a warning that the remaining battery power is insufficient, and a slightly used nickel-metal hydride battery can be used continuously even under heavy load. become. Therefore, by specifying the battery voltage VO of the battery 2 in the medium load state, the battery capacity of the nickel-metal hydride battery having a lower battery voltage than the alkaline battery can be sufficiently increased without discriminating the type of the battery 2. Can be used up. Further, since the medium load state is one of the actual operation modes of the electronic devices 1 and 21, there is no need to add external components such as a dummy load, and the number of components increases, the cost of circuit components increases, and power consumption increases. Wasteful consumption can be avoided.

[0031]

As described above, according to the electronic apparatus of the first and second aspects, the battery level specified only when the specified battery level is smaller than the battery level displayed on the display unit. By updating and displaying the remaining battery power indicated by the mark, unlike a conventional electronic device, it is possible to avoid an erroneous display due to a change in the load of the battery. The amount can be matched to the actual battery level.

According to the electronic device of the third aspect,
When the detected load amount is in a light load state, the remaining battery level is specified by comparing each light load threshold voltage with the detected battery voltage, and when the detected load amount is in a heavy load state, each heavy load state is determined. By comparing the load threshold voltage and the detected battery voltage to identify the remaining battery level and displaying the identified remaining battery level on the display unit, particularly when the variation in the battery load level is large, The remaining battery level can be more accurately specified as compared with the conventional method of specifying the remaining battery level using a fixed threshold voltage regardless of the amount of battery load. Also, when the battery load shifts from the heavy load state to the light load state, even if the battery voltage returns and rises accordingly, even if the battery voltage is higher than the threshold voltage for the heavy load, By switching to the threshold voltage of, it is possible to avoid an erroneous display of the remaining battery level that the provisional battery remaining capacity in the specified light load state is larger than the battery remaining capacity in the heavy load state. The remaining battery level matching the remaining level can be displayed.

According to the electronic device of the fourth and fifth aspects, when the control unit shifts from the light load state to the heavy load state, the control unit shifts the electronic device to the medium load state, and detects the state at the time of the medium load state. By stopping the transition to the heavy load state when the set battery voltage is lower than the preset threshold voltage, the battery voltage is instantaneously greatly reduced when the transition to the heavy load state is performed. Therefore, it is possible to reliably prevent the malfunction of the electronic device due to the above. In addition, by specifying the battery voltage in the middle load state, the battery capacity of the nickel-metal hydride battery having a lower battery voltage characteristic than that of the alkaline battery can be fully used without determining the type of the battery. Further, since the medium load state is one of the actual operation modes of the electronic device, there is no need to add external components such as a dummy load, and the number of components increases, the cost of circuit components increases, and wasteful power consumption occurs. Can be avoided.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of electronic devices 1 and 21 according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram illustrating an example of a remaining amount display when the remaining battery level is “sufficient”;

FIG. 3 is an explanatory diagram showing an example of a remaining amount display when the remaining battery level is “medium”.

FIG. 4 is an explanatory diagram showing an example of a remaining amount display when the remaining battery level is “small”.

FIG. 5 is a flowchart of a battery voltage display process A in the electronic device 1.

FIG. 6 is a flowchart of a battery voltage display process B in the electronic device 21.

FIG. 7 is a flowchart of a process of determining whether to shift to a heavy load state via a medium load state in the electronic devices 1 and 21.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electronic device 2 Battery 3 Voltage detection part 4 Input part 5 Monochrome LCD 6 Color LCD 7 Backlight 8 Memory 9 Control part 10 Display remaining amount storage part 11 Threshold storage part 11a Light load threshold storage part 11b Heavy load Threshold storage unit VO battery voltage

Claims (5)

[Claims] 1. An electronic device that operates by using a built-in battery as a drive source, comprising: a voltage detection unit that detects a battery voltage of the battery; a display unit that digitally displays a remaining battery level of the battery; A control unit for specifying the remaining battery level based on the detected battery voltage and displaying the remaining battery level on the display unit, wherein the control unit displays the specified remaining battery level on the display unit. An electronic apparatus characterized in that the displayed remaining battery level is updated and displayed with the specified remaining battery level only when the remaining battery level is lower than the specified remaining battery level. 2. A display remaining amount storage unit for storing the battery remaining amount displayed on the display unit, and a threshold value storing unit for storing a plurality of threshold voltages for specifying the battery remaining amount. The control unit compares the detected battery voltage with each threshold voltage stored in the threshold storage unit to specify the temporary battery remaining amount, Only when the remaining battery level is smaller than the remaining battery level stored in the display remaining level storage unit, the temporary remaining battery level is updated and displayed on the display unit as the remaining battery level, and the new remaining level is displayed in the display remaining level storage unit. 2. The system according to claim 1, wherein the battery level is updated and stored.
Electronic device as described. 3. An electronic device that operates using a built-in battery as a drive source, wherein the voltage detector detects a battery voltage of the battery, a load detector that detects a load on the battery, A display unit for digitally displaying the remaining battery level, and a light-load threshold storage unit for storing a plurality of light-load threshold voltages for identifying the remaining battery level in a light-load state; A heavy load threshold that is set to a voltage lower than each of the light load threshold voltages and stores a plurality of heavy load threshold voltages for specifying the remaining battery level in a heavy load state. A value storage unit, and a control unit for specifying the remaining battery level based on the detected battery voltage and displaying the remaining battery level on the display unit, wherein the control unit includes the detected load amount. When light load condition The remaining battery level is specified by comparing the light-load threshold voltage with the detected battery voltage. When the detected load amount is a heavy load, each of the heavy-load threshold voltages and the detection are determined. An electronic device, wherein the remaining battery level is specified by comparing the detected remaining battery voltage. 4. An electronic device that operates in at least three modes, at least in a light load state, a medium load state, and a heavy load state, using the battery as a driving source, wherein the control unit switches the light load state from the light load state. When shifting to the heavy load state, the electronic device is shifted to the medium load state, and when the detected battery voltage is lower than a preset threshold voltage during the medium load state, the electronic apparatus is switched to the heavy load state. 4. The electronic device according to claim 1, wherein the transition to the load state is stopped. 5. An electronic device that operates in at least three modes, using the battery as a driving source, and is roughly divided into a light load state, a medium load state, and a heavy load state, wherein the control unit is configured to switch the light load state from the light load state When shifting to the heavy load state, the electronic device is shifted to the medium load state, and when the detected battery voltage is lower than a predetermined threshold voltage during the medium load state, 2. The operation of the electronic device is stopped.
4. The electronic device according to any one of items 1 to 3.