JP2003153459A - Electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic apparatus in which a battery can be used effectively. SOLUTION: As a driving power supply, an auxiliary battery 34 is provided in addition to a main battery 32. The main battery 32 is normally used as a power supply and only when a peak current flows, the peak current is controlled by means of a microcomputer 12 such that power is supplied from both the main battery 32 and the auxiliary battery 34 according to the timing. Even if a peak current flows when the residual quantity of the main battery 32 is low, occurrence of voltage drop can be prevented and the main battery 32 can be used effectively to the end.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic device, and more particularly to an electronic device such as a digital camera, a video camera and a mobile terminal which uses a battery as a power source.

[0002]

2. Description of the Related Art In a portable electronic device such as a digital camera, a battery is generally used as a power source, and when the capacity of the battery is exhausted, the battery does not operate. Therefore, in such a portable electronic device, the remaining battery amount is constantly monitored and the remaining battery amount is displayed (Japanese Patent Laid-Open No. 2000-125236, etc.).

[0003]

However, even if the battery capacity remains, if the capacity is small, there is a problem that the voltage drops due to the peak current flowing and the system goes down. As a result, there is a problem that the battery cannot be used effectively until the end. Further, in the case of a rechargeable battery, there is a problem that inactivation occurs due to the battery not being used up to the end in this way and the performance of the battery deteriorates.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an electronic device which can effectively use a battery.

[0005]

In order to achieve the above object, the present invention provides a main battery as a supply source of driving power in an electronic device using a battery as a power source,
An electronic device comprising: an auxiliary battery that supplies drive power together with the main battery; and a control unit that controls the drive power to be supplied from the auxiliary battery in accordance with a timing when a peak current flows. provide.

According to the present invention, the auxiliary battery is provided in addition to the main battery, and the auxiliary battery is used together with the main battery in accordance with the timing when the peak current flows. As a result, even if the peak current flows when the remaining amount of the main battery is low, the occurrence of voltage drop can be suppressed. Further, this allows the battery to be used effectively to the end, and in the case of a rechargeable battery, deactivation of the battery can be prevented.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of an electronic device according to the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram showing the configuration of a digital camera to which the present invention is applied. The digital camera 10 according to the present embodiment can select a “shooting mode” and a “playback mode” with a mode dial provided on a camera body (not shown), and still shooting and playback of a shot image are performed according to the selection. be able to.

When the "shooting mode" is set by the mode dial, still shooting becomes possible. When the user presses the shutter button (not shown) provided on the camera body, the microcomputer 12 detects this and Controls the execution of the still shooting operation.

That is, the microcomputer 12 performs auto focus (AF) control and automatic exposure control, and images the subject light on the light receiving surface of the solid-state image sensor (CCD) 16 via the taking lens 14.

The CCD 16 converts the subject light imaged on the light receiving surface into signal charges of an amount corresponding to the amount of light. The signal charges thus accumulated are sequentially read out as a voltage signal corresponding to the signal charges and applied to the correlated double sampling circuit (CDS circuit) 18. Then, here, the R, G, and B signals for each pixel are sampled and held, amplified, and then converted into digital signals by an A / D converter. This digital signal is temporarily stored in the memory 20, and the signal processing circuit (YC processing circuit) 22
Added to.

The signal processing circuit 22 performs predetermined image processing such as synchronization processing for simultaneously converting input dot-sequential R, G, B signals, white balance adjustment, gamma correction, and YC signal processing. The luminance signal Y and the chroma signals Cr and Cb (Y) created by the YC signal processing of the signal processing circuit 22.
The C signal) is stored again in the memory 20, and then sequentially compressed by the JPEG compression circuit 24 and recorded in the recording medium (memory card) 26. This completes the shooting.

On the other hand, when the "reproduction mode" is set by the mode dial, the image file recorded on the recording medium 26 is read. The compressed data of the read image file is decompressed by the JPEG decompression circuit 28 into a YC signal, which is expanded and stored in the memory 20. The image signal developed in the memory 20 is sized by the signal processing circuit 22 to the image size for display, and then the NTS
It is converted into a C type color composite video signal and output to the LCD display unit 30. As a result, the captured image recorded on the recording medium 26 is displayed on the LCD display unit 30.

By the way, as shown in FIG. 1, the digital camera 10 is provided with two batteries, a main battery 32 and an auxiliary battery 34, as power sources. Normally, the main battery 32 is used as a power source, and the auxiliary battery 34 is used together with the main battery 32 as needed. The microcomputer 12 controls the supply of power from the two batteries 32 and 34. That is, the auxiliary battery 3
By controlling ON / OFF of the switch 36 connected to 4, the power is supplied from the auxiliary battery 34 in addition to the main battery 32.

Here, the power supply from the auxiliary battery 34 is controlled so as to be performed at the timing when the peak current flows. For example, since the peak current flows when the photographing lens 14 is AF-driven by the AF motor 38, the power is supplied from the auxiliary battery 34 in conjunction with the control of the AF motor 38. At this time, the microcomputer 12 causes the AF motor 3 to
Power is supplied from the auxiliary battery 34 in advance before the driving of the motor 8 and the supply is stopped after the AF motor 38 is stopped.

In addition to this, the peak current flows, for example, during strobe charging or zoom motor driving, and the microcomputer 12 controls the supply of power from the auxiliary battery 34 in conjunction with these operations. That is, ON / OFF of the switch 36 is controlled.

Since the timing at which the AF motor 38 is driven, the timing at which the strobe is charged, the timing at which the zoom motor is driven, etc. are known, the microcomputer 12 interlocks with these controls and outputs from the auxiliary battery 34. Pre-programmed to control the supply of power.

Further, the microcomputer 12 uses the main battery 3
2 and the voltage of the auxiliary battery 34 are measured, and the remaining amount of each battery is calculated based on the measured voltage. Then, the remaining amount of each battery is individually displayed on the LCD display unit 30. The user can grasp the remaining amounts of the main battery 32 and the auxiliary battery 34 by checking the display on the LCD display unit 30.

The operation of the digital camera 10 of the present embodiment configured as described above is as follows.

When a power button provided on a camera body (not shown) is pressed, the digital camera 10 is supplied with power from the main battery 32 and the system is activated. Normally, the digital camera 10 has a main battery 32.
Each function operates by the power supply from. The power is also supplied from the auxiliary battery 34 only when the peak current flows. This control is performed as follows.

As described above, the peak current flows when the AF motor 38 is driven during AF control. This case will be described as an example.

When the shutter button is pressed and the AF control is started, the microcomputer 12 controls the power supply in synchronization with the driving timing of the AF motor 38. That is, when it is necessary to drive the AF motor 38 to focus the photographing lens 14 as a result of distance measurement to the subject,
As shown in FIG. 3, first, the switch 36 is closed (step S1), and power is supplied from the auxiliary battery 34 (step S2). Then, after the supply of power from the auxiliary battery 34 is started, the AF motor 38 is started after a lapse of a predetermined time (step S3). Then, after the AF motor 38 is stopped (step S4), the switch 3
6 is opened (step S5), and the supply of power from the auxiliary battery 34 is stopped (step S6). After this, power is supplied only from the main battery 32 to operate the
The same control is performed each time the F control is performed, and power is supplied from the auxiliary battery 34.

In this way, the peak current flows even when the capacity of the main battery 32 is reduced by controlling the power supply from the auxiliary battery 34 at the timing when the peak current flows. It is possible to prevent the voltage drop due to this (see FIG. 2). As a result, even if the capacity of the main battery 32 is reduced, the digital camera 10 can be operated stably, and the main battery 32 can be used up to the end effectively. Further, in this case, in the case of the rechargeable battery, it is possible to prevent inactivation due to not using up the battery.

Since the remaining amounts of the main battery 32 and the auxiliary battery 34 are displayed on the LCD display section 30, the user confirms the displays to confirm the remaining amounts of the main battery 32 and the auxiliary battery 34. be able to. Then, by replacing the main battery 32 or the auxiliary battery 34 based on this display, it is possible to always ensure stable operation.

This display may be always displayed on the LCD display section 30 or may be displayed as necessary. That is, for example, a battery check button may be provided on the main body, and the remaining battery level may be displayed on the LCD display unit 30 only when the battery check button is pressed. Also, the battery voltage may be measured only when the battery check button is pressed.

The remaining battery level may be displayed not on the LCD display section 30 used for reproducing the photographed image, but on a dedicated display section.

Further, in the present embodiment, the power source is controlled whenever the peak current flows and the auxiliary battery 34 is also used. However, the power source is supplied only when the capacity of the main battery 32 becomes low. You may make it implement control.

That is, as shown in FIG.
2 measures the voltage of the main battery 32 (step S
11) When the voltage value of the main battery 32 becomes equal to or lower than a preset specified value (step S12),
Power supply control is started (step S13). This allows
The auxiliary battery 34 can be used efficiently.

Furthermore, in the present embodiment, an example in which the present invention is applied to a digital camera has been described. However, the application of the present invention is not limited to this, and a peak current flows so that a voltage is applied. It can be applied to all electronic devices in which drops occur. For example, the present invention can be applied to an electronic device such as a digital camera or a mobile phone having a function of reproducing a music file such as MP3 having only the still image capturing function. In this case, in a digital camera having a music file reproducing function, a peak current flows when a loud sound is output, and a peak current flows when a radio wave is output in a mobile phone or the like. In addition, the present invention can be similarly applied to electronic devices such as digital cameras, video cameras, notebook computers, and PDAs having a moving image shooting function.

In the present embodiment, the auxiliary battery 3
There is only one 4, but a plurality may be used.

[0031]

According to the present invention, the auxiliary battery is provided in addition to the main battery, and the auxiliary battery is used simultaneously with the main battery at the timing when the peak current flows, whereby the peak current flows. Also, the voltage drop can be suppressed and the battery can be used effectively until the end. Further, in this case, in the case of the rechargeable battery, inactivation of the battery can be prevented.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a digital camera to which the present invention is applied.

FIG. 2 is an explanatory diagram of the operation of the digital camera of this embodiment.

FIG. 3 is a flowchart showing a procedure of power supply control.

FIG. 4 is a flowchart showing a procedure for starting power supply control.

[Explanation of symbols]

10 ... Digital camera, 12 ... Microcomputer, 14 ... Photographing lens, 16 ... Solid-state image sensor (CCD), 18 ... Correlated double sampling circuit (CDS circuit), 20 ... Memory, 22
... signal processing circuit (YC processing circuit), 24 ... JPEG compression circuit, 26 ... recording medium (memory card), 28 ... JP
EG expansion circuit, 30 ... LCD display unit, 32 ... Main battery, 34 ... Auxiliary battery, 36 ... Switch, 38 ... A
F motor

Claims (4)

[Claims] 1. An electronic device using a battery as a power source, a main battery serving as a supply source of driving power, an auxiliary battery supplying driving power together with the main battery, and the auxiliary battery according to a timing at which a peak current flows. An electronic device comprising: a control unit that controls so that driving power is supplied from the electronic device. 2. The electronic device according to claim 1, wherein the control unit performs control so that drive power is supplied from the auxiliary battery in advance before the peak current flows. 3. A main battery voltage measuring means for measuring a voltage of the main battery, wherein the control means adjusts to a timing at which the peak current flows when the voltage of the main battery becomes equal to or lower than a preset specified value. The electronic device according to claim 1 or 2, wherein the electronic device is controlled so that drive power is supplied from the auxiliary battery. 4. An auxiliary battery voltage measuring means for measuring the voltage of the auxiliary battery, and an arithmetic means for obtaining the remaining amount of the auxiliary battery based on the voltage of the auxiliary battery measured by the auxiliary battery voltage measuring means. The electronic device according to claim 1, 2 or 3, further comprising: a display unit that displays the remaining amount of the auxiliary battery obtained by the calculation unit.