JP2996076B2 - Charge control 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 charge control device, and more particularly to a charge control circuit for a main battery and an auxiliary battery of a device requiring data retention.

[0002]

2. Description of the Related Art A conventional charge control circuit independently charges a main battery and an auxiliary battery.

[0003]

As described above, in the conventional charge control circuit, only the charge control of the main battery is performed, and the charge control of the auxiliary battery is performed regardless of the state of charge of the main battery and the state of the device. However, charging was performed independently (trickle charging) with a smaller current than the main battery. Therefore, when both the main battery and the auxiliary battery are discharged, even if recharging of the main battery and the auxiliary battery is started at the same time, the main battery is fully charged because the charging time until the full charge of the auxiliary battery is long. However, the auxiliary battery was not fully charged at the same time.

[0004] In particular, in a device having only a means for displaying only the state of charge of the main battery, the main battery alone is fully charged even if the charging device is turned off. However, there is a disadvantage that the charging is performed from the main battery or the auxiliary battery is in an insufficiently charged state, and the holding time and the operating time are shorter than when both are fully charged.

The present invention has been made in view of the above-mentioned conventional circumstances, and accordingly, an object of the present invention is to provide a novel charge control device capable of solving the above-mentioned drawbacks inherent in the prior art. Is to do.

[0006]

In order to achieve the above object, a charging control device according to the present invention comprises a normal charging circuit for a main battery, a trickle charging circuit, a main battery charging control circuit, and a normal charging circuit for an auxiliary battery. And a trickle charging circuit and an auxiliary battery charging control circuit, and the device has an output monitoring circuit for an output of an auxiliary power supply for holding data, and the auxiliary power supply charging control circuit controls the output monitoring. There is no output of the auxiliary power supply by having means for selectively controlling whether the auxiliary battery is controlled by the main battery charge control circuit or by forcibly performing trickle charging depending on the presence or absence of the output of the auxiliary power supply by the circuit. In this case, a means for performing charging control depending on the main battery charging control circuit of the auxiliary battery and forcibly performing trickle charging when there is an output is provided.

[0007]

Next, a preferred embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention.

Referring to FIG. 1, in a device 20 driven by an external power supply 1 or a secondary battery, the device 20 includes, as a secondary battery, a main battery 2 used for driving the device and holding data; And an auxiliary battery 3 used only for the battery. When the external power supply 1 is connected, the main battery charge control circuit 6 monitors the voltage of the main battery 2 via a voltage monitoring line 8 and, if the monitored voltage is lower than a specified value depending on the state of the main battery 2, a control signal At 11, the normal charging circuit 9 is selected,
The ordinary charging circuit 9 performs ordinary charging of the main battery 2 for a predetermined time. If the monitoring voltage is higher than a specified value, the trickle charging circuit 10 is selected by the control signal 11, and the trickle charging circuit 10 always performs trickle charging on the main battery 2.

At this time, an output monitoring circuit 12 for monitoring the output state (presence / absence of output) of the auxiliary power supply 5, which is a power supply for holding data, monitors the auxiliary power supply 5 immediately before the external power supply 1 is connected. When there is no output, the auxiliary battery charging control circuit 7 controls the selection of the charging circuit of the auxiliary battery 3 and the control thereof according to the control of the main battery charging control circuit 6 by the control signal 11 and the trickle with the ordinary charging circuit 13. This is performed for the charging circuit 14. That is, if the main battery charging control circuit 6 selects the normal charging circuit 9, the auxiliary battery charging control circuit 7 selects the charging circuit for the auxiliary battery 3 and the normal charging circuit 13 and also controls the start and end of charging. This is performed in synchronization with the main battery charge control circuit 6. If the main battery charging circuit 6 selects the trickle charging circuit 10, the trickle charging circuit 14 is also selected as the charging circuit for the auxiliary battery 3.

When the output of the auxiliary power supply 5 is detected by the output monitoring circuit 12 and when the external power supply 1 is disconnected from the device 20, the main battery charging control circuit 6
Regardless of the operation of the trickle charging circuit 1
4 is selected and executed.

The auxiliary power supply 5 is configured such that, when the device 20 needs to hold data in the memory unit 15, the main battery 2 or the auxiliary battery 3 can always output even when the main power supply 4 is turned off.

However, when the external power supply 1 is not connected and the main battery 2 and the auxiliary battery 3 reach the discharge end voltage,
The output of the auxiliary power supply 5 is stopped, the device 20 is completely stopped, and the data holding operation is also stopped. However, when the external power supply 1 is connected, the main battery charge control circuit 6 and the auxiliary battery control circuit 7
, And the charging circuits 9, 10, 13, and 14 can be controlled, and the main power supply 4 and the auxiliary power supply 5 also start operating.

At this time, by adopting a configuration in which a delay occurs between the power supply time to the auxiliary battery control circuit 7 and the output time of the auxiliary power supply 5, the output monitoring circuit 12 causes the output of the auxiliary power supply 5 to output during this delay time. It is possible to detect that the vehicle has stopped, and to notify the auxiliary battery output control circuit 7.

Therefore, the output monitoring circuit 12 can identify that the main battery 2 and the auxiliary battery 3 are discharged.

It goes without saying that the same applies to a quick charging circuit instead of a normal charging circuit as a charging circuit for the main battery and the auxiliary battery. Furthermore, as a charging circuit for the main battery and the auxiliary battery, a normal charging circuit,
It is also possible to add a quick charging circuit in addition to the trickle charging circuit.

The main power supply 4 and the auxiliary power supply 5 have a function of stabilizing and outputting the voltages of the main battery 2 and the auxiliary battery 3 , respectively.

[0018]

As described above, according to the present invention,
When the main battery and the auxiliary battery both reach the end-of-discharge state and perform recharging, the charging method of the main battery and the auxiliary battery is made the same, and the main battery and the auxiliary battery are made the same. When the charging of the battery is completed, the auxiliary battery is also controlled so that the charging is completed. Therefore, if the display of the charging state of the main battery indicates that the charging is completed, both the main battery and the auxiliary battery can be always fully charged. .

Therefore, even if the device is operated with the main battery at the same time when the main battery is fully charged, it is not necessary to supply a charging current from the main battery to the auxiliary battery. The effect that the holding time from the state and the operation time can be guaranteed is obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 external power supply 2 main battery 3 auxiliary battery 4 main power supply 5 auxiliary power supply 6 main battery charge control circuit 7 auxiliary battery charge control circuit 8 voltage monitoring line 9 normal charge circuit 10 trickle charge circuit 11 ... Control signal 12 ... Output monitoring circuit 13 ... Normal charging circuit 14 ... Trickle charging circuit 15 ... Memory unit 16 ... H / W unit 17 ... Charging unit 20 ... Device

Claims (3)

(57) [Claims] 1. An apparatus requiring data retention,
A charging control circuit for charging a main battery and an auxiliary battery, a first normal charging circuit and a first trickle charging circuit as a plurality of charging circuits for the main battery, and selecting and charging these charging circuits A main battery charging control circuit for controlling, a second normal charging circuit and a second trickle charging circuit as a plurality of charging circuits for the auxiliary battery, and an auxiliary battery charging control circuit for selecting and controlling these charging circuits. Has,
The auxiliary battery charge control circuit is a charge control device that determines whether or not to perform a control operation according to the main battery charge control circuit based on the presence or absence of an output of the auxiliary battery.
The charge control circuit monitors the voltage of the main battery and checks the remaining amount.
Charging by the first ordinary charging circuit or the first
Means for selecting whether charging is performed by a trickle charging circuit
The first ordinary charging circuit is selected by the selecting means.
Control means for controlling the start and end of charging when
And an auxiliary power supply for data retention in the device.
An output monitoring circuit for monitoring the output;
The control circuit is configured to stop the output of the auxiliary power supply by the output monitoring circuit.
When the main battery charge control circuit detects that the
The selection of the electric circuit and the control of the start and end of charging
Means for the electric circuit and the output monitoring circuit
If the output of the auxiliary power supply is detected, the second
Means for forcibly selecting and controlling the trickle charging circuit of
The main battery charging control circuit selects a normal charging circuit.
If the auxiliary battery charge control circuit is
A normal charging circuit for the main battery charging control circuit.
If the road has selected the trickle charging circuit, the auxiliary battery
The charge control circuit uses a trickle charge circuit to charge the auxiliary battery.
A charge control device that controls to select a road . 2. A plurality of charging circuits for the main battery, wherein a first quick charging circuit is used instead of the first normal charging circuit, or the first normal charging circuit and a first quick charging circuit are used.
Using a first quick charging circuit in addition to the trickle charging circuit described above, and using a second quick charging circuit instead of the second normal charging circuit as the plurality of charging circuits for the auxiliary battery, or The charging control device according to claim 1, further comprising a second quick charging circuit in addition to the normal charging circuit and the second trickle charging circuit. 3. The charging control device according to claim 1 , wherein a delay occurs between a power supply time to the auxiliary battery control circuit and an output time of the auxiliary power supply.