JP3105797B2 - Battery judgment device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery determination device for determining the type and remaining capacity of a battery.

[0002]

2. Description of the Related Art Conventionally, various types of electronic devices using a battery as a power supply have been provided. However, in such a type of battery device, when the battery is consumed beyond a certain limit, an inoperable state or unstable operation is obtained. The battery needs to be replaced before entering such a state. In order to respond to such a request, a technique for determining the remaining capacity of a battery has been proposed.

FIG. 4 is a block diagram showing a configuration of an electronic device to which this kind of technology is applied. In this electronic device, the CPU 8 and the ROM
9. Power is supplied to main components such as the display controller 12, the VRAM 13, and the serial communication unit 14. For this DC-DC converter 5, an AC adapter 30
Alternatively, the voltage from battery 1 is supplied, but AC
When the adapter 30 is not connected, this DC-DC
The converter 5 supplies power to the main components depending on the power supply from the battery 1. Therefore, in this electronic device, the output voltage of the battery 1 is converted into a digital signal by the A / D converter 6, and the CPU 8 turns on the power based on the digital signal (DC-DC in the configuration of FIG. 4).
The time change of the output voltage of the battery 1 during the time when the converter 5 starts operating and the power supply to the main components is started is monitored, and the remaining capacity of the battery 1 is determined based on the monitoring result. If the capacity is not sufficient, a warning is issued to prompt the user to replace the battery.

Next, a method for determining the remaining capacity of a battery according to the prior art will be described with reference to FIG. FIG.
FIG. 7 illustrates a temporal change in the output voltage of the battery 1 when the power is turned on at a certain time t _{0 and} after a certain time has elapsed, and the power is turned off at a time t ₃ ;
(A) is an output voltage waveform when the remaining capacity of the battery 1 is sufficient, and (b) is an output voltage waveform when the remaining capacity of the battery 1 is not sufficient. Vth1 and Vth
th2 is a lower limit value and an upper limit value of the output voltage of the battery 1 required to obtain a normal operation in this electronic device.

As shown in FIG. 5, a difference in the remaining capacity of the battery 1 appears as a difference in a time gradient of a change in the output voltage of the battery when the power is turned on. Therefore, in this prior art, when the AC adapter 30 is not used,
When the power is turned on (the operation of the DC-DC converter 5 is started), the CPU 8 outputs the output voltages V ₁ and V ₂ of the battery 1 at time t1 and time t2 after the power is turned on.
/ D converter 6 and a voltage drop amount ΔV = V ₁ −V ₂ of the battery 1 based on these values (in FIG. 5, ΔV = V ₁ −V ₂ ).
Va or ΔVb), when the voltage drop ΔV is equal to or greater than a predetermined reference value, the remaining capacity of the battery 1 is sufficient. When the voltage drop amount ΔV is less than the reference value, the remaining capacity of the battery 1 is insufficient. It is determined that the battery is used.

On the other hand, when the AC adapter 30 is connected to the terminal 2, the DC
-Since power is not supplied to the DC converter 5, the remaining capacity cannot be determined by the above method. Therefore, in this case, when the power is turned on, the CPU 8 detects this and turns on the switch 4 to turn on the dummy resistor 3.
Then, a current is supplied from the battery 1 to determine the remaining capacity in the same manner as described above. Here, the dummy resistor 3 has such a resistance that when the switch 4 is turned on, a current equal to the total current consumption of the electronic device flows. Accordingly, the determination of the remaining capacity of the battery 1 in this case is performed by the above-described A
The determination of the remaining capacity when the power is turned on in a state where the C adapter 30 is not used is performed under exactly the same conditions.

The above-described conventional technique for determining the remaining capacity of a battery is disclosed in Japanese Unexamined Patent Publication No. 2-218978.
No. 6,009,045.

[0008]

Generally, the discharge characteristics of a battery differ depending on the type of battery. Therefore, in an electronic device that uses a battery as a power source, it is not enough to simply detect insufficient remaining capacity of the battery, and it is required to change the way of warning of insufficient remaining capacity according to the detected remaining capacity and the type of battery used. For that purpose, it is necessary to detect the type of the battery. As a means for this, a method of identifying the type of the battery based on the difference in the outer shape of the battery is also conceivable. However, this method can be applied only when the device design side designs a dedicated battery pack for each battery type and provides a difference in the outer shape of the battery. It cannot be applied to devices that use AA or AA batteries.

[0009] Accordingly, it has been studied whether or not the type of battery cannot be detected by the above-mentioned conventional technology. However, it is extremely difficult to detect the type of battery using such a technique. That is, in the above-described conventional technology, when determining the remaining capacity, only the current corresponding to the total current consumption of the electronic device is supplied to the battery, so that the discharge characteristics are similar even if the type of the battery is different. In this case, the voltage drop amount of the battery is slightly changed, and it is extremely difficult to detect that the type of the battery has changed due to such a small difference. Further, when the remaining capacity is abundant, even if the discharge characteristics greatly differ between the types of batteries, only a small difference in the amount of voltage drop due to the discharge occurs, so that it is difficult to detect the type of the batteries. Furthermore, in the above-described conventional technology, when the remaining capacity of the battery is abundant, the change in the voltage drop of the battery due to the discharge is very small, so that it is not only difficult to detect the type of the battery, but also to determine the remaining capacity. Will also be inaccurate.

The present invention has been made in view of the circumstances described above, and it is a first object of the present invention to provide a battery determination device capable of identifying not only the remaining capacity of a battery but also the type of the battery. . Another object of the present invention is to provide a battery determination device capable of accurately calculating the remaining capacity of a battery even when the remaining capacity of the battery is abundant.
The purpose is.

[0011]

The invention according to claim 1 is
A battery determination device mounted on an electronic device that uses a battery as a power supply, and a discharge circuit that supplies a constant current equal to or more than the current consumption of the electronic device to the battery when power is supplied to the electronic device. Determining means for performing discharge of the battery by the discharge circuit, determining a battery type or remaining capacity based on a voltage drop amount of the battery due to the discharge ,
Detects battery removal or replacement, and stores
Pond missing detecting means, wherein the determining means comprises:
When the power of the device is turned on, the contents held by the
The battery has been removed or replaced.
The gist of the present invention is a battery determination device that determines the type of the battery only when the battery type is determined . Invention according to claim 2
Is a battery determination device mounted on an electronic device that uses a battery as a power supply, and a discharge circuit that supplies a constant current equal to or more than the current consumption of the electronic device to the battery when power is supplied to the electronic device. For each type of battery, and for each remaining capacity of each battery, the output voltage value of the battery in a state where the discharge circuit does not discharge and the output voltage value in a state where the discharge circuit discharges Storage means for storing the output voltage value of the battery, and discharging of the battery by the discharge circuit, the output voltage of the battery when the discharging is not performed, and the output of the battery when the discharging is performed The gist of the present invention is a battery determination device comprising: determination means for determining a voltage and determining the type or remaining capacity of the battery based on the determination result and the contents stored in the storage means.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

A. First Embodiment FIG. 1 is a block diagram showing a configuration of an electronic device using a battery determination device according to a first embodiment of the present invention. In this electronic device, a DC / DC converter 18 receives a power supply from a main battery 19 to generate a constant level power supply voltage Vcc.
Supply to The supply of the power supply voltage Vcc by the DC / DC converter 18 is performed by supplying a power ON control signal from the CPU 13 to the DC / DC converter 18.

The CPU 13, the I / O address decoding unit 14, the missing battery detection unit 15, the A / D converter 1
6. The large current discharge circuit unit 1B constitutes the battery determination device according to the present embodiment, and the main battery 19 is a determination target of the battery determination device.

The battery missing detector 15 has a built-in register, detects whether the main battery 19 has been detached from the apparatus via the switch 1A, and stores the detection result in the register as battery missing information data. .

The A / D converter 16 detects the voltage level of the main battery 19 and outputs digital data of about 8 to 16 bits (hereinafter referred to as main battery voltage level data) representing the voltage level.

The CPU 13 makes an I / O access to the battery exhaustion detector 15 and the A / D converter 16 via the I / O address decoder 14, thereby transmitting the above-mentioned battery exhaustion information data and main battery level data to the data bus. D.
Received via B and executes the analysis process. In the figure, A and B are address buses. The CPU 13
Performs I / O access to the missing battery detection unit 15 via the I / O address decoding unit 14, thereby performing ON / OFF control of the large current discharge circuit unit 1B. Here, the large current discharge circuit section 1B is configured to allow a constant current equal to or more than the current consumption of the electronic device to flow to the main battery 19 when turned on.

CPU 13, I / O address decoding unit 1
4. Battery missing detector 15, A / D converter 16, DC
For the / DC converter 18, the backup power supply 1
The power is supplied from C. Therefore, they can always operate.

FIG. 2 is a flowchart showing the operation of the CPU 13 in the present embodiment. Hereinafter, the operation of the present embodiment will be described with reference to FIG.

When the operator turns on the power switch 11 and attempts to start up the electronic device, a power ON request signal is generated by the power switch unit 12. CPU 13
Detects this power-on request signal (step 2
1) Prior to the generation of the power supply voltage by the DC / DC converter 18 and the start of its supply to the logic system circuit 17 (step 28), each processing after step 22 shown in FIG. 2 is executed.

First, the CPU 13 operates as follows:
The battery missing information data stored in the register is checked to determine whether there is any evidence that the main battery has been removed or replaced with a new battery in the past (step 2).
2). If there is no trace, DC
The / DC converter 18 is activated to start the generation of the power supply voltage and its supply to the logic circuit 17 (step 28).

On the other hand, if there is evidence that the main battery has been discharged or that a new battery has been replaced, the battery discharge detection unit 15 is accessed via I / O to turn on the large current discharge circuit unit 1B for a certain period of time. The state is set, and a large current is caused to flow from the main battery 19 (step 23). Further, the CPU 13 measures each voltage value of the main battery 19 before and after the discharge by taking in the main battery level data output from the A / D converter 16 at each time before and after the discharge (step 24).

Here, in a system memory (not shown) of the electronic device, information indicating a voltage drop amount when a large current discharge is performed is stored as a database for each of various batteries. Therefore, the CPU 13 obtains the voltage drop amount of the voltage value of the main battery 19 before and after the discharge measured in step 24, and compares and verifies this voltage drop amount with the voltage drop amounts corresponding to various batteries in the database (step 24). 25), the type of the main battery 19 is identified by this comparison verification, and the type of the identified battery is stored in the battery attribute register in the system memory (steps 26 and 2).
7). Then, the DC / DC converter 18 is started, and the generation of the power supply voltage and its supply to the logic circuit 17 are started (step 28).

Thereafter, when the remaining capacity of the main battery 19 is detected, the contents of this battery attribute register are referred to, and a warning of insufficient remaining capacity or the like is issued in a manner corresponding to the type of the main battery. Becomes In the flow shown in FIG. 2, one of the two types of batteries, a manganese dry battery and a Ni-Cd secondary battery, is identified. However, a database of voltage drop amounts for three or more types of batteries is prepared. If the voltage drop amounts of the main battery 19 are compared with those, it goes without saying that it is possible to identify three or more types of batteries.

As described above, according to the present embodiment, since the type of the battery can be identified, it is possible to issue a warning such as a shortage of the remaining capacity of the battery in a manner corresponding to the identified type of the battery. Can be. In the above description, only the identification of the type of the battery has been described. However, the remaining capacity of the battery may be detected by a method similar to the above-described conventional technique.

In the present embodiment, the main battery 19
The type of the battery was identified by passing a large current through the battery, but the identification of the type of the battery is performed only when there is evidence of a missing battery or the like. Therefore, unnecessary consumption of the capacity of the main battery 19 can be prevented.

B. Second Embodiment FIG. 3 shows the configuration of a second embodiment of the present invention. In the above-described first embodiment, disconnection or replacement of the main battery 19 is detected by the switch 1A, and discharge of the main battery 19 is performed only when there is evidence of disconnection or replacement of the main battery when the electronic device is powered on. did. On the other hand, in the present embodiment, detection of disconnection or replacement of the main battery 3D is not performed, and
The PU 33 unconditionally performs I / O access to the discharge control unit 39 when the power of the electronic device is turned on, thereby operating the large current discharge circuit unit 3B. That is, in the present embodiment, the function is simplified as compared with the first embodiment.

In the first embodiment, the type of the battery is identified by discharging the main battery 19 by the large current discharging circuit unit 1B. However, in the present embodiment, the large current discharging circuit unit 3B is used.
The discharge by B detects not only the type of the main battery 3D but also the remaining capacity. That is, it is as follows.

First, similarly to the first embodiment, in this embodiment, when the power of the electronic device is turned on, the CPU 33 is turned off.
The main battery 1 is controlled by the large current discharging circuit 3B under the control of
9 is performed, and the A / D converter 35 measures each voltage value of the main battery 3D at each time before and after the discharge. The determination of power ON is performed by the CPU 33 detecting that the power switch 31 has been turned ON via the switch detection unit 32.

In this embodiment, the output voltage value of the battery and the large current discharge in the state where the large current discharge is not performed are performed for each type of battery and for each remaining capacity of each battery. The information indicating the output voltage value of the battery in the state of being stored is stored in a system memory (not shown) as a database.

When the CPU 33 in this embodiment obtains each voltage value before and after the discharge of the main battery 3D as described above, the CPU 33 compares and verifies each of these voltage values with this database and verifies the main battery 3D. Calculate both type and remaining capacity.

Then, the CPU 33 accesses the display control section 36 via the I / O address decoding section 34 via I / O, and displays the remaining capacity of the main battery 3D on the display device 37. When the remaining capacity falls below a certain limit, a warning message indicating that fact is displayed on the display device 37. In this case, what remaining capacity the warning message is displayed, and what the content of the warning message is, is selected according to the identification result of the type of the main battery 3D.

As described above, according to the present embodiment, there is an effect that the type of the battery and the estimation of the remaining capacity of the battery can be simultaneously performed using the same hardware configuration. Further, since the remaining capacity is estimated based on the amount of voltage drop of the battery before and after the large current discharge, the remaining capacity can be accurately estimated even when the remaining capacity of the battery is abundant.

[0034]

As described above, according to the present invention, the amount of voltage drop of a battery due to a large current discharge is measured, so that the type of battery can be identified based on the measurement result. In addition, there is an effect that a warning such as a shortage of the remaining capacity of the battery can be issued by an appropriate method according to the type of the battery. According to the invention,
Since the remaining capacity of the battery is estimated by measuring the amount of voltage drop of the battery due to the large current discharge, there is an effect that the remaining capacity can be accurately estimated even when the remaining capacity of the battery is abundant. (Claims 1 to 3). Further, according to the present invention, it is possible to simultaneously identify the type of battery and estimate the remaining capacity with a simple configuration (claim 2). According to the invention,
Since the type of the battery is identified by the large current discharge only when the battery is detected to be disconnected, there is an effect that the wasteful consumption of the battery capacity can be prevented (claim 2).

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an electronic device using a battery determination device according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing an operation of the embodiment.

FIG. 3 is a block diagram illustrating a configuration of an electronic device using a battery determination device according to a second embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of an electronic device using a conventional device for determining the remaining capacity of a battery.

FIG. 5 is a waveform chart showing the operation of the same device.

[Explanation of symbols]

 13, 33 CPU (determination means) 14, 34 I / O address decoding unit 15 Battery missing detection unit 16, 35 A / D converter 1B, 3B Large current discharge circuit unit 19, 3D Main battery

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁷ , DB name) G01R 31/36 H01M 10/48 H02J 7/00

Claims (2)

(57) [Claims] 1. A battery judging device mounted on an electronic device powered by a battery, wherein a constant current equal to or more than a current consumption of the electronic device is supplied to the battery when power is supplied to the electronic device. A discharging circuit that flows, a discharging unit that discharges the battery by the discharging circuit, a determining unit that determines a type or a remaining capacity of the battery based on a voltage drop amount of the battery due to the discharging, and that the battery is disconnected or replaced. And keep the detection result
Battery detection means, wherein the determination means is configured to switch the battery when the electronic device is powered on.
The content held by the disconnection detecting means is determined, and the disconnection or disconnection of the battery is determined.
Indicates the type of battery as long as replacement has been detected.
Cell determination apparatus characterized by judging the kind. 2. A battery judging device mounted on an electronic device powered by a battery, wherein a constant current equal to or more than a current consumption of the electronic device is supplied to the battery when power is supplied to the electronic device. A discharge circuit to be flown, an output voltage value of the battery in a state where discharge by the discharge circuit is not performed, and a state in which discharge is performed by the discharge circuit for each type of battery and for each remaining capacity of each battery. Storage means for storing the output voltage value of the battery at the time, and discharging the battery by the discharge circuit, the output voltage of the battery when the discharge is not performed and the output voltage of the battery when the discharge is performed A battery determination device comprising: a determination unit configured to determine an output voltage of a battery and determine a type or a remaining capacity of the battery based on a result of the determination and contents stored in the storage unit.