JPH09160680A - Battery-operated equipment and battery-operated equipment control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform operation control corresponding to the characteristics of a battery without burdening a user by controlling the driving of a unit based on a voltage value and a monitor resistance value measured by a measurement means. SOLUTION: At the time of activating a certain unit, a CPU 10 reads the voltage values Va1 and Vb1 of both terminals of a monitor resistor 24 by using A/D converters 26 and 28, and after optional time, reads the voltage values Va2 and Vb2 of both terminals of the monitor resistor 24 by using the A/D converters 26 and 28 again. Then, after calculating the value of the battery internal resistor 20a of the battery 20, the voltage Vb3 after supplying power is calculated. In this case, the power is not supplied in the case that a calculated predicted voltage Vb3 after activating the unit is lower than the operatable voltage of a system and a unit power supply control part 14 is made to supply power in the case of being higher. As a result, the operation control corresponding to the characteristics of the bakery is performed without burdening the user.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery-operated device that operates using a battery as a power source.

[0002]

2. Description of the Related Art Conventionally, a battery-operated device that operates using a battery as a power source determines the output voltage of the battery or the output voltage of the power supply circuit in order to determine whether the capacity (remaining amount) of the battery is sufficient for the device to operate. Is being measured. When the measured voltage becomes equal to or lower than a certain fixed voltage, operation control such as limiting the operation of the device or stopping the operation is performed. In other words, if the power supply voltage falls below the guaranteed operating range due to sudden changes in the device load, internal (memory, etc.) data may be destroyed, or abnormal operation may occur. Motion control is performed.

On the other hand, in a battery-operated device, generally, different types of batteries having various characteristics (alkaline batteries, manganese batteries, NiCd batteries, etc.) can be used. Batteries have different voltage changes (decreases) when the load (current) changes, depending on their characteristics. Therefore, even if the load on the battery-operated device is the same, the battery voltage may exceed a certain voltage depending on the battery used, and normal operation can be continued as it is, or the operation must be limited or stopped. There will be a situation where it will not be.

For this reason, conventionally, in order to stably operate the equipment, the types of batteries that can be used are limited (the users of the equipment are forced to use the batteries), and the voltage corresponding to the characteristics of the battery is used as a reference. A method of performing operation control or switching the battery type to be used by switch setting etc. by allowing the user of the device to determine the battery to be used.

If the types of batteries that can be used are not limited so as not to place a burden on the user of the device, it is recommended to use batteries with low performance (the voltage changes greatly when the load changes). Moreover, a design with an excessive operation margin is performed.

[0006]

As described above, in the conventional battery-operated device, the type of battery that can be used is limited, or the user determines the type of battery to be used and sets the switch to use the device. It was a burden to the person. Further, when the types of usable batteries are not limited, there is a problem that the operating life is shortened because the device is designed with an excessive operating margin.

The present invention has been made in consideration of the above-mentioned circumstances, without limiting the types of batteries that can be used,
An object of the present invention is to provide a battery-operated device capable of performing operation control according to the characteristics of a battery without imposing a burden on the user.

[0008]

According to the present invention, there is provided a battery for supplying electric power to a unit constituting an apparatus, a monitor resistor connected in series with the battery for measuring an output voltage value of the battery, and The measuring means comprises a measuring means for measuring a voltage value between both ends of the monitor resistor and the ground, and a controlling means for controlling driving of the unit based on the voltage value measured by the measuring means and the resistance value of the monitor resistor. It is characterized by

Further, the control means calculates the battery internal resistance value of the battery when starting the drive of the unit, and starts the drive of the unit obtained based on the battery internal resistance value. Based on the output voltage value of the battery in such a case, whether to start driving the unit is controlled.

Further, the control means calculates a battery internal resistance value of the battery, and based on the output voltage value of the battery when the driving of the unit obtained based on the battery internal resistance value is stopped, It is characterized by controlling whether or not the driving of the unit is stopped.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic configuration of a battery-operated device according to this embodiment. As shown in FIG. 1, the battery-operated device includes a CPU 10, a memory 12, and an I / O.
Device (unit power supply control unit) 14, battery 20, load (R
1) 22, a monitor resistor (Rf) 24, and A / D converters 26 and 28. The battery-operated device shown in FIG. 1 is, for example, a portable information device, and is provided with various input / output (IO) units such as a liquid crystal display and a floppy disk drive. A load when an IO unit such as a liquid crystal display or a floppy disk drive is driven (turned on) is represented as a load (Rl) 22.

The CPU 10 controls the entire battery-operated equipment. The CPU 10 is the A / D converter 2
The power supply of the unit is determined based on the voltage value notified from 6, 28 and the load change value which is stored in the memory 12 and fluctuates depending on the ON / OFF of the power supply control target unit. .

The memory 12 stores programs, data, etc. that define the operation of the CPU 10. Memory 12
The program stored in includes a control program for performing operation control according to the battery voltage for various units that constitute the battery-operated device. The memory 12
In the data stored in, the load change value (estimated current consumption value I
The data indicating 1) is included.

I / O device (unit power supply controller) 14
Turns on / off the drive of the unit whose power supply is to be controlled, according to the result determined by the CPU 10. The display device 15 is composed of a liquid crystal display or the like, and displays according to an instruction from the CPU 10.

The battery 20 supplies electric power to various units constituting a battery-operated device. Battery 20
The output voltage (battery voltage) inside the battery of V, and the battery internal resistance 20a that changes due to driving of the unit (Rd)
And

The load 22 (Rl) represents a power consuming portion inside the device when a power source such as a liquid crystal display or a floppy disk drive is turned on. The value of the load 22 varies depending on the driving unit.

The monitor resistor 24 (Rf) is for measuring the output voltage and current of the battery 20, and is connected in series to the output of the battery 20. The resistance value Rf of the monitor resistor 24 is a known value.

The A / D converters 26 and 28 measure the voltage values Va and Vb between both ends of the monitor resistor 24 and the ground, convert them into digital data which can be processed by the CPU 10, and output the digital data.

Next, the operation of the battery-operated device in this embodiment will be described with reference to the flowchart shown in FIG. First, start a unit (turn on the power)
When trying to do so, the CPU 10 uses the A / D converter 2
6, 28 are used to read the voltage values Va1, Vb1 across the monitor resistor 24 (RF) (step S1). After an arbitrary time, the CPU 10 again
Using the D / D converters 26 and 28, the monitor resistor 24
The voltage values Va2 and Vb2 at both ends of (RF) are read (step S2).

Here, the CPU 10 compares the voltage values Va1 and Vb1 obtained by the first measurement with the voltage values Va2 and Vb2 obtained by the second measurement, respectively. If the values are the same, the CPU 10 again uses the A / D converters 26 and 28 to cause the voltage values Va2 and V2 across the monitor resistor 24 (RF).
Read b2.

That is, when the voltage values are the same after two measurements, the battery internal resistance 20a
This is because it is not possible to obtain the value of, and the expected voltage value after the unit power is turned on. Normally, the load fluctuates when the CPU 10 is operating, so that the voltage value is different when the second measurement is performed after an arbitrary time.

Voltage value Va across the monitor resistor 24 twice
2, Vb2 is measured, the CPU 10 calculates the battery internal resistance 20a (R) of the battery 20 based on the following equation (1).
The value of d) is calculated (step S4). The resistance value Rf of the monitor resistor 24 is a known value, is stored in the memory 12 in advance, and is read as needed.

[0023]

[Equation 1]

Next, the CPU 10 uses the value (Rd) of the battery internal resistance 20a calculated based on the equation (1),
An expected value of the voltage Vb3 after the power supply to the unit to be used is turned on is calculated based on the following equation (2) (step S5). At this time, the CPU 10 causes the memory 12 to change the load value that fluctuates depending on the on / off state of the power supply of the unit about to be turned on, that is, the expected current value I1.
To read and execute the operation.

[0025]

(Equation 2)

If the expected voltage Vb3 calculated after the unit is started is lower than the operable voltage of the system (step S6), the CPU 10 does not turn on the unit that was about to turn on (unit power source). The controller 14 is not caused to turn on the power), and the display device 15 is caused to display a message for notifying that the power cannot be turned on (step S8).

On the other hand, when the calculated expected voltage Vb3 after the unit is activated exceeds the operable voltage of the system (step S6), the CPU 10 causes the unit power control unit 14 to turn on the unit. Power is turned on (step S7), and the operation is continued.

In this way, when the unit is to be started, the battery internal resistance 20a of the battery 20 is obtained, and whether or not the unit can be started using this battery internal resistance value 20a is actually determined. It can be determined without operating. That is, the drive control of the unit (whether or not to turn it on) is performed in response to the difference in battery characteristics due to the difference in battery type, by obtaining the voltage drop amount of the battery 20 immediately before starting the unit. You can
At this time, no burden is imposed on the user.

Then, by starting the unit and predicting a circuit voltage when a new load is applied, a sudden change (decrease) in the circuit voltage due to a sudden change (increase) in the load current caused by adding a new load. It is possible to prevent the abnormal operation of the circuit and the destruction of data due to. Therefore, it is not necessary to design the device with an excessive operating margin.

In the above description, the operation when the power of the unit is turned on is explained. However, when the battery voltage drops, it is possible to cut off the power of some units and continue the operation as a device. it can.

That is, the CPU 10 has the monitor resistor 24.
Based on the voltage values Va and Vb at both ends of, the voltage drop of the battery 20 is determined. When the CPU 10 determines that if the currently driven unit is continuously used as it is, it will fall below the operable voltage of the system, the CPU 10 disconnects one of the units to extend the device operation. At this time, C
The PU 10 selects the disconnecting unit by using the above-described formulas (1) and (2) so that the minimum necessary load can be released.

Further, in the above-described embodiment, the current value and the like are calculated using the monitor resistor 24, but the current value is directly measured by the hall element or the like and is calculated together with the measurement result of the battery voltage. May be.

[0033]

As described above in detail, according to the present invention, it is possible to perform operation control according to the characteristics of the battery without imposing a burden on the user without limiting the types of batteries that can be used. It is possible.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a battery operated device according to an embodiment of the present invention.

FIG. 2 is a flowchart for explaining operation control for a battery-operated device according to the present embodiment.

[Explanation of symbols]

 10 ... CPU 12 ... Memory 14 ... I / O device (unit power supply control unit) 15 ... Display device 20 ... Battery 20a ... Battery internal resistance 22 ... Load 24 ... Monitor resistance 26, 28 ... A / D converter

Claims (4)

[Claims] 1. A battery for supplying electric power to a unit constituting an apparatus, a monitor resistor connected in series with the battery for measuring an output voltage value of the battery, and both ends of the monitor resistor and a ground. A battery-operated device comprising: a measuring unit that measures a voltage value between them; and a control unit that controls driving of the unit based on the voltage value measured by the measuring unit and the resistance value of the monitor resistor. . 2. The control means calculates a battery internal resistance value of the battery when starting to drive the unit, and starts driving the unit, which is obtained based on the battery internal resistance value. The battery-operated device according to claim 1, wherein whether or not to start driving the unit is controlled based on the output voltage value of the battery in the case of the above. 3. The control means calculates a battery internal resistance value of the battery, and based on an output voltage value of the battery when driving of a unit obtained based on the battery internal resistance value is stopped, The battery-operated device according to claim 1, which controls whether or not the driving of the unit is stopped. 4. An output voltage value of a battery for supplying electric power for operation to an apparatus is measured, a battery internal resistance value of the battery is calculated from the measured output voltage value, and the calculated battery internal resistance value is calculated. Based on the above, the battery operating device control method is characterized in that the output voltage value of the battery at the time of turning on the power of the unit constituting the device is calculated, and the drive of the unit is controlled based on the calculated output voltage value. .