JPH11289680A - Electronic equipment and battery pack - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To enable a user to accurately recognize when the voltage of a secondary battery falls below the minimum operating voltage of an electronic device and to reduce waste of battery capacity. Aim. SOLUTION: In an electronic device 1 which operates using a secondary battery 2a as a power supply, a first detector 1d for detecting a voltage for inhibiting the operation of the electronic device main body, and prohibiting the operation of the electronic device main body. A second detector 3 for detecting a voltage between the voltage and the overdischarge prohibiting voltage of the secondary battery 2a and a display element 5 are provided, and the output of the first detector 1d is used to control the main body of the electronic device. The operation is prohibited and the display element 5 is controlled based on the detection signal of the second detector 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic device suitable for use in, for example, a portable telephone and a battery pack suitable for use in an electronic device such as a portable telephone.

[0002]

2. Description of the Related Art Generally, as shown in FIG. 6, a battery pack 2 having a secondary battery 2a such as a lithium ion secondary battery is used as a power source in a portable telephone set 1, as shown in FIG. In this battery pack 2, the positive electrode of the secondary battery 2a is connected to the positive terminal 2b of the battery pack 2, and the negative electrode of the secondary battery 2a is connected to the negative terminal 2d of the battery pack 2 via the protection circuit 2c. I have.

The operating voltage of the conventional portable telephone 1 is mainly 3.0 V. That is, this mobile phone 1
In the figure, 1a denotes a positive terminal connected to the positive terminal 2b of the battery pack 2, and the positive terminal 1a is connected to the output side by 3.
Connected to the input side of a constant voltage circuit 1b for obtaining a constant voltage of 0V,
The constant voltage of 3.0 V obtained on the output side of the constant voltage circuit 1b is supplied to the circuit of the main body of the portable telephone such as the microcomputer 1c.

The voltage obtained at the positive terminal 1a is supplied to a detection circuit 1d for detecting 3.5V, and a detection signal of the detection circuit 1d is supplied to a microcomputer 1c.

In this case, the conventional portable telephone 1 uses the constant voltage circuit 1b of 3.0 V to generate the internal power supply. An input voltage of 0.3 V to 3.5 V is required. Further, in order for the microcomputer 1c inside the mobile phone 1 to reliably read and write the memory, the power supply voltage of 3.0 V is absolutely not allowed to decrease.

Further, after the power is turned on, when a transition is made from a standby state to a talking state in which a large current is consumed, a certain margin is required because the input voltage drops sharply.
Therefore, in order to ensure the power supply voltage, the battery pack 2
, That is, the input voltage of the constant voltage circuit 1b is 3.
The detection circuit 1d detects whether the voltage is 5 V or less.
Even if the power switch is turned on by e, this mobile phone main body is not operated.

On the other hand, the discharge characteristic of the secondary battery 2a of the battery pack 2 is as shown by a curve a in FIG. 7. When the portable telephone body is not operated at this 3.5V, the secondary battery 2a The battery capacity is wasted even though there is still usable capacity remaining as shown by the diagonal lines in FIG. 7 in FIG. 2a (in FIG. 7, 2.5V is the overdischarge prohibition voltage of the secondary battery 2a). .

In FIG. 6, if is a negative electrode terminal 2d.
And the negative terminal 1f is grounded. Reference numeral 1g denotes a liquid crystal display device that performs various displays of the mobile phone 1. Reference numeral 1h denotes a charging circuit for charging the secondary battery 2a provided in the main body of the mobile phone. A DC voltage is supplied to an input side of the charging circuit 1h, and an output terminal is connected to the positive terminal 1a.

[0009]

Since the conventional portable telephone has the above-described structure, the voltage of the secondary battery 2a of the battery pack 2 used is lower than the minimum operating voltage of the portable telephone 1, for example, 3.5V. In some cases, even if the user turns on the power switch, no operation is performed, so that there is a problem that the user may recognize as a failure.

[0010] In addition, there is a display that uses a liquid crystal display device 1g to indicate that the voltage of the secondary battery 2a of the battery pack 2 is equal to or lower than the minimum operating voltage of the mobile phone 1. There was a problem that it could not be recognized at night due to the liquid crystal display.

As described above, it is useless to use nothing while the battery capacity of the secondary battery 2a remains.

In view of the above, the present invention is intended to allow a user to accurately recognize when the voltage of a secondary battery becomes lower than the minimum operating voltage of an electronic device and to avoid wasting battery capacity. The purpose is to do.

[0013]

SUMMARY OF THE INVENTION According to the present invention, there is provided an electronic device which operates using a secondary battery as a power supply, a first detector for detecting a voltage for inhibiting operation of the electronic device main body,
A second detector for detecting a voltage between a voltage for inhibiting the operation of the electronic apparatus main body and an overdischarge inhibiting voltage for the secondary battery; and a display element, and an output of the first detector is provided. The operation of the electronic device main body is prohibited, and the display element is controlled based on the detection signal of the second detector.

According to the electronic device of the present invention, the second detector for detecting a voltage between the voltage for inhibiting the operation of the electronic device main body and the overdischarge inhibiting voltage for the secondary battery is provided. Since the display element is controlled based on the detection signal of the second detector, when the voltage of the secondary battery becomes equal to or lower than the minimum operation voltage of the electronic device, that is, equal to or lower than the operation prohibition voltage, the user can accurately recognize this. At the same time, the remaining of the battery capacity is used by the display of the display element, and waste can be reduced.

Further, the present invention relates to a battery pack having a secondary battery used as a power supply for operating an electronic device,
A memory for storing information on a voltage at which operation of the electronic device is prohibited, a voltage determining means for determining whether or not the voltage of the secondary battery has become a voltage at which operation of the electronic device is prohibited; And a display element for displaying the result.

According to such a battery pack, it is determined whether or not the voltage of the secondary battery has become a voltage at which the operation of the electronic device is prohibited, and this is displayed on the display element. When the voltage becomes equal to or lower than the minimum operating voltage of the electronic device, the user can accurately recognize the voltage, and the display of the display element uses the remaining battery capacity to reduce waste.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of an electronic apparatus and a battery pack according to the present invention will be described with reference to the drawings. 1 and 5, the portions corresponding to FIG. 6 are denoted by the same reference numerals.

FIG. 1 shows an example in which the electronic apparatus of the present invention is applied to a portable telephone. In this mobile phone 1, as shown in FIG. 1, a battery pack 2 having a secondary battery 2a such as a lithium ion secondary battery is used as a power source.

In this battery pack 2, the secondary battery 2
The positive electrode of the battery pack 2 is connected to the positive terminal 2b of the battery pack 2, and the negative electrode of the secondary battery 2a is connected to the negative terminal 2d of the battery pack 2 via the protection circuit 2c. The overdischarge protection circuit of this protection circuit 2c is operated at, for example, 2.5 V or less.

The operating voltage of the portable telephone 1 of this embodiment is set to 3.0 V as in the prior art. The positive terminal 1a of the mobile phone 1 is connected to the positive terminal 2b of the battery pack 2, and the positive terminal 1a is connected to the input side of a constant voltage circuit 1b for obtaining a constant voltage of 3.0 V on the output side. The constant voltage of 3.0 V obtained at the output side of the voltage circuit 1b is supplied to the circuit of the main body of the portable telephone such as the microcomputer 1c.

The voltage obtained at the positive terminal 1a is supplied to a detection circuit 1d for detecting 3.5 V, and the detection signal of the detection circuit 1d is supplied to the microcomputer 1c.

In this case, in the portable telephone 1 of this embodiment, a constant voltage circuit 1b for obtaining a constant voltage of 3.0 V is used to generate an internal power supply.
Requires an input voltage of 3.3V to 3.5V. Further, in order for the microcomputer 1c inside the mobile phone 1 to reliably read and write the memory, the power supply voltage of 3.0 V is absolutely not allowed to decrease.

Further, after the power is turned on, when a transition is made from a standby state to a talking state in which a large current is consumed, a certain margin is required because the input voltage drops sharply.
Therefore, in order to ensure the power supply voltage, the battery pack 2
, That is, the input voltage of the constant voltage circuit 1b is 3.
The detection circuit 1d detects whether the voltage is 5 V or less. If the voltage is 3.5 V or less, the microcomputer 1c constituting the system controller does not operate the mobile phone main body even if the power switch is turned on by the key input device 1e. To

On the other hand, the discharge characteristic of the secondary battery 2a of the battery pack 2 is as shown by a curve a in FIG. 2. When the portable telephone body is not operated at 3.5V, the secondary battery of the battery pack 2 is not operated. 2a still has usable capacity.

In this embodiment, the positive terminal 1a is connected between a voltage, for example, 3.5 V, for inhibiting the operation of the portable telephone body and an overdischarge inhibiting voltage, for example, 2.5 V, for the secondary battery 2a of the battery pack 2. Voltage point A to point B, for example, 3.5 V
It is connected to the input side of the predetermined voltage detection circuit 3 for detecting 2.6V.

When the predetermined voltage-to-voltage detection circuit 3 detects the voltage A-B between the predetermined voltages, for example, 3.5 V to 2.6 V, this detection signal is supplied to the display control circuit 4, and at this time, The display control circuit 4 controls the light emitting diode LED 5
Is controlled.

[0027] In this case, since the effectively utilizing the remaining capacity of the few remaining secondary batteries 2a in this example, lit for T ₂ for example 100m seconds as shown in FIG. 3, repeated off then between T ₁ for example 5 seconds A blinking display is provided to prompt the user to charge.

The display control circuit 4 stops the blinking display of the light emitting diode 5 when the detection signal of the predetermined voltage A-B is not obtained. Therefore, in this case, the voltage of the secondary battery 2a of the battery pack 2 does not fall below the overdischarge prohibition voltage.

In this case, when a DC voltage is supplied to the charging circuit 1h of the portable telephone 1 and the charging of the secondary battery 2a of the battery pack 2 is started, the display control circuit 4 indicates that charging has started. The blinking display of the light emitting diode 5 may be stopped even when the voltage of the secondary battery 2a is between the voltage points A and B between the predetermined voltages.

Also, in FIG. 1, if is a battery pack 2
The negative terminal 2d is connected to the negative terminal 2d, and the negative terminal 1f is grounded. Reference numeral 1g denotes a display device such as a liquid crystal display device for performing various displays on the mobile phone 1.

Also, in FIG.
1 shows a charging circuit for charging a secondary battery 2a of a battery pack 2 provided in the power supply circuit. A DC voltage is supplied to an input side of the charging circuit 1h, and an output terminal of the charging circuit 1h is connected to a positive terminal 1a. Connect to

The operation related to the power supply of the portable telephone 1 according to the present embodiment will be described with reference to the flowchart of FIG.

The discharge characteristic of the secondary battery 2a of the battery pack 2 when using the mobile phone 1 according to the present embodiment is as shown by a curve a in FIG.
The mobile phone is operated from the fully charged state of a to the operation prohibition voltage of the mobile phone main body, for example, 3.5V. That is, as shown in FIG. 4, when the mobile phone 1 is operated, a voltage detection circuit 1d for detecting a voltage of 3.5V and voltage points A and B between predetermined voltages of 3.5V to 2.6V are detected. The voltage detection circuit 3 between predetermined voltages is operated (step S1).

At this time, the voltage of the secondary battery 2a is 3.5 V
Is detected (step S2), and 3.5V
In the above case, this detection is continued, and when this voltage becomes 3.5 V, the process proceeds to step 3 and the light emitting diode 5
Starts blinking, and prompts the user to charge the secondary battery 2a and prohibits the operation of the mobile phone body.

At this time, it is determined whether or not the charging of the secondary battery 2a has started (step S4), and whether or not the voltage of the secondary battery 2a has reached an overdischarge prohibition voltage, for example, 2.6V which is close to 2.5V. (Step S
5).

In this case, when the charging of the secondary battery 2a is started, the blinking display of the light emitting diode 5 is stopped, and this series of operations is ended.

When the voltage of the secondary battery 2a becomes 2.6 V, the blinking display of the light emitting diode 5 is stopped, and the above-described series of operations is terminated.

According to the present embodiment, a voltage between point A and point B, for example, between a voltage that inhibits the operation of the mobile phone body, for example, 3.5 V or less and an overdischarge inhibition voltage of the secondary battery 2 a, for example, 2.5 V or less, The light emitting diode 5 is blinked based on a detection signal of the predetermined voltage detection circuit 3 for detecting the voltage between the predetermined voltages of 0.5 V to 2.6 V. When the voltage becomes equal to or lower than the minimum operating voltage of the mobile phone, that is, equal to or lower than the operation prohibition voltage, the user can accurately recognize the malfunction and there is no inconvenience that the malfunction is recognized.

The blinking display of the light emitting diode 5 uses the battery capacity of the rechargeable battery 2a, so that the remaining capacity of the rechargeable battery 2a is effectively used and the waste of the battery capacity is reduced. There are benefits that can be.

FIG. 5 shows an embodiment of the battery pack of the present invention. FIG.
This is an example in which the present invention is applied to a telephone pack 2 used in the present embodiment.

In FIG. 5, reference numeral 2a denotes a secondary battery such as a lithium ion secondary battery. The positive electrode of the secondary battery 2a is connected to the positive electrode terminal 2b of the battery pack 2, and the secondary battery 2a is The negative electrode is connected to the negative terminal 2d of the battery pack 2 via the protection circuit 2c.

The overdischarge protection circuit of the protection circuit 2c operates at, for example, 2.5 V or less. The configuration of the mobile phone 1 in the example of FIG. 5 is the same as that of a generally used mobile phone, and the operating voltage is 3.0 V.

The positive terminal 1a of the portable telephone 1 is connected to the positive terminal 2b of the battery pack 2, and the positive terminal 1a is connected to the output side to obtain a constant voltage of 3.0 V on the output side.
b, and supplies a constant voltage of 3.0 V obtained at an output side of the constant voltage circuit 1b to a circuit of the main body of the portable telephone such as a microcomputer.

In this case, in this portable telephone 1,
Constant voltage circuit 1 for obtaining a constant voltage of 3.0 V to create an internal power supply
Although b is used, since there is a saturation voltage, an input voltage of 3.3 V to 3.5 V is required to output this 3.0 V. Further, in order for the microcomputer inside the mobile phone 1 to reliably read and write data in and from the memory, the power supply voltage of 3.0 V is never allowed to decrease.

Further, after the power is turned on, when a transition is made from the standby state to the talk state in which a large current is consumed, the input voltage suddenly drops, so that a certain margin is required.
The supply voltage from the battery pack 2, that is, the input voltage of the constant voltage circuit 1b needs to be 3.5V.

In FIG. 5, 1f indicates a negative terminal connected to the negative terminal 2d of the battery back 2, and this negative terminal 1f is grounded. Reference numeral 1i denotes a control terminal connected to the control terminal 2e of the battery pack 2, and the control terminal 1i is grounded via a resistor 1j indicating information unique to the mobile phone 1.

The input of a voltage detecting circuit 11 for detecting the voltage of the secondary battery 2a is connected to the microcomputer 12, and the detected voltage value detected by the voltage detecting circuit 11 is supplied to the microcomputer 12.

The microcomputer 12 determines the voltage value from the voltage detection circuit 11, controls the memory 13,
The determination of the information specific to the mobile phone 1 connected to the control terminal 2e, that is, the determination of the type, and the control of the display element 14 such as a light emitting diode provided in the battery pack 2 are performed.

In the memory 13 according to the present embodiment, the portable telephone 1
And voltage information for inhibiting the operation of the mobile phone 1 specified by the unique information, for example, 3.5 V;
The overdischarge prohibition voltage of the secondary battery 2a of the battery pack 2, for example, voltage information slightly higher than 2.5V, for example, 2.6V is stored in advance.

In this case, when the battery pack 2 is used for a plurality of types of mobile phones, the memory 13 stores information unique to the types of the plurality of types of mobile phones and information unique to the plurality of types of mobile phones. The information is stored in the information of the voltage A at which the operation of each mobile phone is prohibited. This is because the voltage A at which operation is prohibited may differ depending on the type of mobile phone.

The display element 14, such as a light emitting diode, controls the voltage of the secondary battery 2a under the control of the microcomputer 12 so that the voltage between the predetermined voltage points A to B (as shown in FIG. 2).
When the point becomes 3.5V to 2.6V, for example, FIG.
In this case, the display is made to blink in a cycle as shown in FIG.

Since the present embodiment is configured as described above, when the portable telephone 1 is connected to the battery pack 2 as shown in FIG. 5, the microcomputer 12 in the battery pack 2 connects the portable telephone 1 to the control terminal 2e. Specific information is obtained by the resistor 1j on the side, and the specific information is referred to the memory 13 to determine the type of the mobile phone 1.
2. A voltage point at which the operation of the mobile phone 1 is prohibited, for example, 3.
Read 5V.

Next, when the voltage detection circuit 11 in the battery pack 2 notifies the microcomputer 12 that the voltage of the secondary battery 2a has reached the operation inhibition voltage A point, for example, 3.5 V, the microcomputer 12 The computer 12 blinks the display element 14, such as a light emitting diode, to prompt the user to charge the battery by effectively utilizing the remaining capacity of the secondary battery 2a.

In this case, the operation of the mobile phone 1 is prohibited.

Next, the voltage detection circuit 11 outputs the voltage indicated by the point B in FIG.
When 6 V is detected, the microcomputer 12
Stops the blinking display of the display element 14, such as a light emitting diode, so that the secondary battery 2a is not consumed.

That is, in this example, the battery pack 2 automatically determines the type of the connected mobile phone 1 and the voltage (minimum operating voltage) A at which the operation of the connected mobile phone 1 is inhibited, for example, Voltage between point A and point B between 3.5V and the overdischarge prohibition voltage of the secondary battery 2a, for example, 2.5V, for example, 3.
The display element 14 such as a light-emitting diode blinks between 5 V and 2.6 V to prompt charging.

According to this example, the secondary battery 2 of the battery pack 2
The voltage a is an operation prohibition voltage of the mobile phone 1, for example, 3.5 V
In the following cases, the display element 14 such as a light-emitting diode blinks and prompts the user to charge, so that there is an advantage that the user accurately recognizes the failure and does not recognize the failure.

Further, according to this embodiment, since the light-emitting body such as the light-emitting diode is displayed blinking, it is easy to understand even at night or the like, and there is an advantage that the remaining capacity of the secondary battery 2a can be effectively used.

Although the above-described embodiment has been described with respect to an example in which the present invention is applied to a mobile phone and a battery pack used in the mobile phone, the present invention is similarly applied to other electronic devices and battery packs used in other electronic devices. Of course, it can be applied.

Further, the present invention is not limited to the above-described example, and it goes without saying that various other configurations can be adopted without departing from the gist of the present invention.

[0061]

According to the present invention, when the voltage of the secondary battery of the battery pack becomes equal to or lower than the operation prohibition voltage of the electronic device, a display element such as a light emitting diode displays and prompts the user to charge. There is an advantage that this can be accurately recognized and not recognized as a failure.

Further, according to the present invention, since the display is performed by the display element such as the light emitting diode, it is easy to understand even at night or the like, and there is an advantage that the remaining capacity of the secondary battery can be effectively used.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating an example of an embodiment of an electronic apparatus of the present invention.

FIG. 2 is a diagram for describing the present invention.

FIG. 3 is a diagram for explanation of the present invention.

FIG. 4 is a flowchart for explaining FIG. 1;

FIG. 5 is a configuration diagram showing an example of an embodiment of the battery pack of the present invention.

FIG. 6 is a configuration diagram illustrating an example of a conventional mobile phone.

FIG. 7 is a diagram for explaining FIG. 6;

[Explanation of symbols]

1 mobile phone, 1a, 2b positive terminal, 1b, 1
1 voltage detection circuit, 1c, 12 microcomputer, 1f, 2d negative electrode terminal, 1h charging circuit,
i, 2e control terminal, 1j resistor, 2 battery pack, 2a secondary battery, 2c protection circuit, 3 voltage detection circuit between predetermined voltages, 4 display control circuit, 5,14
{Display element, 13} Memory

Claims (4)

[Claims] An electronic device that operates using a secondary battery as a power supply, a first detector that detects a voltage that inhibits operation of the electronic device body, and a voltage that inhibits operation of the electronic device body. A second detector that detects a voltage between the overdischarge prohibition voltage of the secondary battery and a display element;
An electronic device, wherein the operation of the electronic device main body is inhibited by an output of the first detector, and the display element is controlled based on a detection signal of the second detector. 2. A battery pack having a secondary battery used as a power supply for operating an electronic device, a memory storing information of a voltage for inhibiting operation of the electronic device, and a voltage of the secondary battery being the electronic device. A battery pack comprising: a voltage discriminating means for discriminating whether or not the voltage has been set to prohibit the operation of the above; and a display element for displaying the discrimination result of the voltage discriminating means. 3. The battery pack according to claim 2, further comprising electronic device discriminating means for storing information of a voltage for inhibiting operation of a plurality of types of electronic devices in the memory and discriminating the connected electronic device. A battery pack characterized by the following. 4. The battery pack according to claim 2, further comprising an overdischarge prohibition voltage detecting means for detecting an overdischarge prohibition voltage of the secondary battery, wherein a detection signal of the overdischarge prohibition voltage detection means is provided. A battery pack wherein the display of the display element is stopped.