JPS63198547A - Electronic equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to electronic equipment, particularly a primary power source, a means for charging a rechargeable secondary battery with the power of the primary power source, and a method for charging the charging means. The present invention relates to an electronic device having means for controlling operations according to a predetermined procedure.

[Prior Art] Rechargeable batteries such as Ni-Cd"if batteries and lead batteries are widely used as secondary batteries for various electric circuits and devices.

In devices such as tape recorders and calculators, a commercial power source or a solar battery is used as a primary power source, and a secondary battery is charged and used with the power of the primary power source.

In a rechargeable battery like the one described above, a charging procedure is used in which the state of charge is detected while measuring the terminal voltage of the battery, and the charging radio waves are controlled according to the state of charge.

Furthermore, the charging time of the battery is managed by a timer or the like, and control is performed to prevent charging from continuing for more than a predetermined period of time.

Furthermore, it is known that a so-called memory effect exists depending on the type of secondary battery. This means that when shallow charging and discharging are repeated, the discharge characteristics deteriorate more than when deep charging and discharging are repeated. In order to avoid this problem and improve the discharge characteristics, a charging procedure has been considered in which the secondary battery is once completely discharged and then charging is started.

[Problems to be solved by the invention] As mentioned above, when controlling the charging procedure based on a certain procedure, a control device using a microprocessor or a control device configured by combining logic circuits is required. Become. As a power source for such a control device, a primary power source such as a commercial power source is usually used.

However, due to power outages, the primary power supply is cut off,
If a voltage drop occurs for any reason, the charging procedure by the control device is interrupted. Then, when the output of the primary power source is restored again, the charging procedure is repeated from the beginning.

For example, if a timer is managed to prevent charging for more than a predetermined time, the timer will be reset due to a power outage, resulting in charging for more than the predetermined time.

Furthermore, in devices that require a procedure for discharging a secondary battery, there is a problem in that the procedure from discharging to charging is repeated, prolonging the processing time.

Means for Solving Problem E] In order to solve the following problems, 1.
In an electronic device having a secondary power source, a means for charging a rechargeable secondary battery with the power of the primary power source, and a means for controlling the charging operation of the charging means according to a predetermined procedure, an output state of the primary power source is provided. A configuration is adopted in which the secondary battery is used as a power source for the control means when the output state of the primary power source detected by the means becomes insufficient for the control operation of the control means. did.

[Function] According to the above configuration, even if there is a problem with the output of the primary power source, the power source of the control device is backed up by the output of the secondary battery being charged, so the problem of repeating the charging procedure from the beginning is solved. There is no.

[Example] Hereinafter, the present invention will be described in detail based on an example shown in the drawings.

FIG. 1 shows the structure of a power supply section of an electronic device employing the present invention.

In the figure, reference numeral 1 is a commercial AC power supply, which supplies power to the -order power supply 2. The primary power supply 2 is a transformer 21 for transformation,
It is composed of a rectifying diode 22, a smoothing capacitor 23, and a load resistor 24, and is used as a charging control system, which will be described later, and as a charging power source for a secondary battery. The primary power source 2 may be externally attached to the device in the form of an AC adapter or the like.

Reference numeral 3 denotes a constant current circuit which, based on an input signal through a signal line 9, controls a secondary battery 1 such as a lead battery or a Ni-Cd battery.
Determine the charging current of 2. The charging current output from the constant current circuit 3 is connected to the secondary battery 12 via a diode 8 for backflow prevention.
It is designed to be powered by.

Reference numeral 4 denotes a three-terminal regulator composed of an integrated circuit and the like for generating power for the control circuit 10 and the A/D converter 41 from the primary power source.

Also, code 5 is a secondary battery! Control circuit lO and A/D from 2
This is a three-terminal regulator that generates power for the converter and backs up when the primary power goes out.

The outputs of the three-terminal regulators 4.5 are each connected to the power supply terminal of the control circuit 1O via a backflow prevention diode 6.7.

The control circuit 10 is composed of a logic circuit, a microprocessor, etc., and controls charging of the secondary battery 12.The control circuit 10 is a control unit that controls the entire electronic device including this power supply unit. It may be something common.

The basic charge control function of the control circuit 10 is to perform a charging operation for a predetermined time using a built-in timer for a predetermined time;
and detects the terminal voltage of the secondary battery 12 via the A/D converter 11, and when the state of charge indicated by the terminal voltage becomes fully charged, the charging current is cut off by controlling the signal line 9. .

Further, in this embodiment, a detection circuit 14 is provided which is configured of a series connection of a resistor R and a Zener diode ZD in order to detect the presence or absence of primary power supply. The output of this detection circuit 14 is input to the control circuit 10 via a signal line 13.

Next, the operation in L-scriptor acid will be explained.

Voltage is supplied from the primary power supply device 2 to the three-terminal regulator 4 by the AC voltage source 1, and the control circuit 1O and the A/D converter 11 start operating via the diode 6.

Here, if the secondary battery 12 is not fully charged, the control circuit l
O detects this via the A/D converter 11, turns on the constant current circuit 3 via the control line 9, starts a built-in timer for a predetermined time (for example, 75 minutes), and charges the secondary battery 12. Start.

The charging current is controlled according to the charging state detected by the A/D converter 11.

If the AC voltage source l is no longer supplied due to a power outage or the like during charging, this is detected by the primary power supply detection circuit 14, and the signal line 13 notifies the control circuit 10 that the primary power supply has ceased. Ru.

That is, when the output of the primary power supply 2 is sufficiently large, a high level voltage equal to the Zener potential is generated across the Zener diode ZD, but when the input of the detection circuit 14 decreases, the signal line 13 becomes low level. . This makes it possible to detect a drop in the output of the primary power source.

When a decrease in the output of the primary power source 2 is detected as described above, the control circuit IO stops the above-mentioned timer and starts charging 7ft2.
Detection of the charging voltage of the next battery 12 is stopped.

At this time, the secondary battery 12 controls the 3-terminal regulator 1/-5.
If the secondary battery 12 is charged to the extent that it can supply power to the control circuit IO and the A/D converter 11 via the diode 7, the control circuit 10 and the A/D converter 11 continue to operate.

When the supply of the AC voltage source l is resumed again, -n'If
The supply of primary power is resumed by the f source device 2, the detection line 13 is set to high level by the primary power supply detection circuit 14, and the control circuit 10 restarts counting of the 75-minute timer and measures the voltage of the secondary battery 12. is restarted by the A/D converter 11.

Depending on whether the voltage of the secondary battery 12 is detected by the A/D converter 11 as charging completion or the 75-minute timer ends, the control circuit 10 detects charging completion and controls the constant current circuit 3. It is turned off via line 9 to end the charging process.

According to the above configuration, even if the primary power supply is cut off due to a power outage, the timer that measures the charging time will not be reset.
The control state is backed up by the charging battery until energization is started again.

Then, when the primary power source is restored, the timer is started midway and the charging process is continued. If the control circuit 10 has a sufficiently small current consumption, the charging process can be restarted and the secondary battery 12 can be fully charged without changing the state of charge of the secondary battery 12.

FIG. 1 shows an example of a charging method that uses a timer to control the charging time, but considering the memory effect,
In the method of discharging the secondary battery and then charging it,
A configuration as shown in FIG. 2 is conceivable.

In FIG. 2, a transistor TR is connected to the child terminal of the secondary battery 12.
A discharge circuit 15 is connected thereto.

This transistor TR is connected to the signal line 16 by the control circuit 10.
is made conductive by a high level input through the discharge resistor R1.
The secondary battery 12 is discharged via.

In the structure L, voltage is supplied from the primary power supply 2 to the three-terminal regulator 4 by the AC voltage source l, and the voltage is supplied to the three-terminal regulator 4 via the diode 6 to the control circuit lO and the A/D converter 11.
Power is supplied to the unit and it starts operating.

Here, the control circuit IO confirms that the primary power supply is being supplied by the detection line 13 from the primary power supply detection circuit 14, and controls the discharge of the secondary battery 12 by setting the secondary battery discharge circuit control line 16 to high. By setting the level, the discharge circuit 15 is turned on and discharge of the secondary battery 12 is started.

When the control circuit 10 detects through the A/D converter 11 that the discharge of the secondary battery 12 is completely completed, the discharge circuit 15 is turned off by setting the secondary battery discharge circuit control line 16 to a low level.

Furthermore, the constant current circuit 3 is turned on via the control line 9, and charging of the secondary battery 12 via the diode 8 is started. The procedure for charging the secondary battery 12 is the same as that shown in FIG.

When charging is detected by voltage detection of the secondary battery 12, the control line is turned off, the charging current of the secondary battery 12 is cut off, and charging is completed.

Here, when the supply of the AC voltage source 1 is cut off during the charging M control consisting of discharging and charging the secondary battery 12, the primary power supply is supplied from the detection line 13 to the control circuit 10 by the primary power supply detection circuit 14. A decrease in output is reported.

As a result, the control circuit 10 stops detecting the voltage of the secondary battery 12. At this time, the secondary battery 12 connects the control circuits IO and A via the 3-terminal regulator 5 and the diode 7.
/D converter 11 until the secondary battery 12 is supplied with power.
If the charge remains, the control circuit IO and the A/D converter 11 stand by with the control interrupted by backup power supply from the secondary battery 12.

When the supply of the AC voltage source 1 is restarted, the supply of primary power is restarted by the secondary power supply device 2, and the primary power supply detection circuit 1
4, the detection line 13 becomes high level, the control circuit IO detects that the primary power supply has resumed, restarts the voltage detection of the secondary battery 12 by the A/D converter 11, and resumes the previous discharging and charging procedures. return.

If the output of the primary power source decreases during the charging period, charging is interrupted and backup is performed in the same manner as in the case of FIG.

Even in the above configuration, the charging procedure is only interrupted.
Since the process is resumed from the point where it was interrupted when the primary power source is restored, processing time is not wasted and the secondary battery is not overcharged.

Although an AC power source has been exemplified as the primary power source in the above, similar effects can be obtained even when a power source such as a solar cell is used as the primary power source.

[Effects of the Invention] As is clear from 1-1 below, according to the present invention, there is provided a primary power source, a means for charging a rechargeable secondary battery with the power of the primary power source, and a charging operation of the charging means. In an electronic device having a means for controlling according to a predetermined procedure, means for detecting an output state of the primary power source is provided, and the output state of the primary power source detected by the means is insufficient for the control operation of the control means. Since a configuration is adopted in which the secondary battery is used as a power source for the control means when a situation such as There is no place I9! Charging processing can be performed without wasting time or placing a burden on the secondary battery.

[Brief explanation of the drawing]

FIGS. 1 and 2 are circuit diagrams showing different configurations of the power supply section of an electronic device employing the present invention, respectively. ! ...AC power supply 2--primary power supply 3...
constant current circuit

Claims (1)

[Claims] An electronic device having a primary power source, a means for charging a rechargeable secondary battery with the power of the primary power source, and a means for controlling the charging operation of the charging means according to a predetermined procedure.
Means for detecting the output state of the secondary power source is provided, and when the output state of the primary power source detected by this means becomes insufficient for the control operation of the control means, the secondary battery is connected to the power source of the control means. An electronic device characterized by being used as an electronic device.