JP3199550B2 - Battery check circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called battery check circuit used for checking the state of a power supply in various electric devices, and more particularly to outputting a so-called reset signal for controlling the operation of an electric circuit in the electric device to an initial state. The present invention relates to a battery check circuit provided with a reset circuit that performs resetting.

[0002]

2. Description of the Related Art Conventionally, in various electric circuits, when a voltage state of a power supply cannot guarantee a normal operation of an electric device, an appropriate warning is issued or a so-called prohibition of the operation of the electric device. In order to output a battery check signal, various so-called battery check circuits for detecting and judging whether or not the voltage state of the power supply is in an appropriate state that can guarantee the normal operation of the electric device have been proposed or put into practical use.

Further, when it is necessary to detect that the electric equipment is under a specific condition, for example, when replacing a power supply battery, it is necessary to control the return of an electric circuit in the electric equipment to an initial state. Various reset circuits that detect a specific condition and output a so-called reset signal have been proposed or put into practical use.

[0004] Therefore, an electric device that requires both the battery check circuit and the reset circuit as described above is configured to include, for example, an electric circuit as shown in FIG.

FIG. 3 is an electric circuit diagram showing an essential part of an example of a conventionally known electric device provided with a battery check circuit and a reset circuit, and includes a so-called power supply terminal 1 for outputting a power supply voltage to be detected and a so-called power supply terminal 1. A battery check circuit 2 comprising a series connection of a first voltage detection means 3 and a detection switch 4 and a resistor 5 between the ground and a reset circuit 6 comprising a second voltage detection means 7 and a resistance 8 are provided. Note that the detection switch 4 is normally kept open, and is closed when it is desired to detect whether or not the power supply voltage is in a proper state that can guarantee the normal operation of the electric device.

When the detection switch 4 is closed, the first voltage detection means 3 outputs the voltage to the power supply terminal 1 and the input terminal 3a.
By comparing the power supply voltage input to the power supply voltage with a minimum voltage value that can guarantee the normal operation of the electric device, that is, a guaranteed reference voltage value set in advance to a so-called guaranteed voltage value, the state of the power supply voltage is determined as the electric device. Is in a proper state to guarantee the normal operation of its output terminal 3b.
Further, it outputs an output signal for performing an inversion operation at the above-mentioned guaranteed reference voltage value, that is, a so-called battery check signal.

The second voltage detecting means 7 is connected to the power terminal 1
And the power supply voltage output to the input terminal 7a and
For example, by comparing a maximum voltage value required to return an electric circuit in an electric device to an initial state, a so-called return voltage value, with a previously set return reference voltage value, the state of the power supply voltage in the electric device is reduced. , An output signal for performing an inversion operation on the basis of the restoration reference voltage value, that is, a so-called reset signal is output from an output terminal 7b of the circuit. Is what you do.

The operation of the first voltage detecting means 3 will not be described when the detection switch 4 is open, and the output terminal 3b of the first voltage detecting means 3 will be in an electrically open state. The power supply voltage output to the power supply terminal 1 via the resistor 5 is applied to the output terminal O1 of the check circuit 2, and is maintained at a high level.

When the detection switch 4 is closed, the above-described comparison operation is performed, and its output terminal 3b is set to a high level when the power supply voltage output to the power supply terminal 1 is equal to or higher than the guaranteed voltage value. Controlled to low level if:
Therefore, the output terminal O1 of the battery check circuit 2 is controlled to the same state as the output terminal 3b, and the signal from the output terminal O1 is an output signal indicating whether or not the normal operation of the electric device can be guaranteed, that is, a so-called battery check signal. used.

On the other hand, the second voltage detecting means 7 does not include a control means such as the detection switch 4 and therefore performs the above-described comparison operation from the time when the power supply voltage is output to the power supply terminal 1 and outputs the same. From the terminal 7b, for example, an output signal is output which becomes high level when the power supply voltage is equal to or higher than the reset voltage value and becomes low level when the power supply voltage is equal to or lower than the reset voltage value. The signal from the output terminal O2 is used as an output signal indicating whether or not it is necessary to control the return of the electric circuit in the electric device to the initial state, that is, a so-called reset signal.

[0011]

As described above, electrical equipment that requires both a battery check circuit and a reset circuit is well known. However, considering the practical use of such electrical equipment, It has the following disadvantages.

As described above, both the battery check circuit and the reset circuit operate on the basis of, for example, the guaranteed voltage value and the reset voltage value. As described above, different conditions are considered, so that different voltage values are usually set.

[0013] For example, the guaranteed voltage value is provided with an operating means by which the electric equipment normally performs some physical action, specifically, a mechanical portion operated by a drive source such as a motor. Is appropriately determined in consideration of the voltage state that can also guarantee the operation described above, and is actually set to a relatively high level.

Also, the return voltage value is different from the above-mentioned guaranteed voltage in consideration of a voltage state which can guarantee the normal operation of the electric circuit itself in the electric equipment, not a voltage state which can guarantee the operation of the action means for performing the physical action. On the other hand, the guaranteed voltage value of the electric circuit itself is usually lower than the guaranteed voltage value of the action means, and is actually lower than the guaranteed voltage value in consideration of the operation of the action means described above. Will be set to the level.

Therefore, when an electric device requiring both a battery check circuit and a reset circuit is put into practical use, a comparison based on each of the guaranteed voltage value and the reset voltage value as shown in FIG. Two voltage detecting means for performing the operation are required, and as a result, there is an inconvenience that the cost of the entire electric device increases.

The present invention has been made in consideration of the above points, and detects whether a voltage state serving as a power supply is, for example, a voltage state that can guarantee normal operation of an electric device by one voltage detecting means. A so-called battery check operation, and a so-called reset operation for detecting whether or not the state of the voltage serving as a power supply is a voltage state where it is necessary to return an electric circuit in the electric device to an initial state. An object of the present invention is to provide a battery check circuit that can reduce the cost of the entire electric device.

[0017]

A battery check circuit according to the present invention has a first terminal and is connected between a power supply terminal from which a first voltage to be detected is output and a ground. The first voltage is divided into at least one second voltage obtained by dividing the first voltage during the selected predetermined period.
A voltage switching means for outputting a voltage, a second terminal electrically connected to the first terminal, and a third terminal, wherein the voltage supplied to the second terminal is compared with a predetermined voltage to thereby provide a third terminal A voltage detection means for outputting an output signal for performing an inversion operation at a predetermined voltage from a third terminal; and a fourth terminal electrically connected to the third terminal.
An electric signal having a terminal and a fifth terminal , supplied to the fourth terminal
Predetermined set to a sufficiently longer time than the predetermined period of
A delay means for outputting only an electric signal whose supply is maintained for more than the delay time from the fifth terminal, and changing the signal output from the third terminal during the predetermined period during which the second voltage is output to the voltage state of the first voltage A signal output from the fifth terminal is used as a first confirmation signal for confirming the voltage state of the first voltage.
It is configured to output as a confirmation signal.

[0018]

In the battery check circuit according to the present invention, since the voltage switching means is connected between the power supply terminal outputting the first voltage to be detected and the ground, the first voltage is always the first voltage. At least one of the divided second voltages is output from the first terminal of the voltage switching means for the selected predetermined period.

Therefore, one voltage detecting means having the second terminal electrically connected to the first terminal has the first voltage,
At least two kinds of voltages, that is, a second voltage, are selectively supplied. As a result, the voltage detecting means performs a comparison operation between a predetermined voltage set in advance and the two kinds of voltages. As a result, two types of output signals for performing the inversion operation at the predetermined voltage are output.

In other words, the first voltage is divided into at least one second voltage by the voltage switching means during the selected predetermined period, and the first voltage is not changed during the period other than the predetermined period, that is, always at the same time. The voltage is compared with the predetermined voltage by the voltage detection means. Therefore, the third terminal of the voltage detection means can output two types of output signals different from each other during a predetermined period during which at least one second voltage is output and at other times. Become.

Further, since the third terminal of the voltage detecting means is electrically connected to the fourth terminal of the delay means, the above two kinds of output signals are basically appropriate for both output signals. After the elapse of the delay time, an attempt is made to output from the fifth terminal.

However, the delay time in the delay means is set to a time sufficiently longer than a predetermined time during which at least one second voltage is output from the voltage switching means, that is, for example, the state of the third terminal is set within the predetermined time. The relationship between the delay time and the predetermined period is set so that even if there is a large variation in the above, the variation does not appear at the fifth terminal. Therefore, the fifth terminal is configured so that two types of output signals are output with delay.
Since one of the two types of output signals is output only within the above-described predetermined period, the fifth terminal receives only the other type, that is, only the output signal output during a period other than the predetermined period. Will be output. In other words, the delay means
Of the electric signal supplied to the fourth terminal from the predetermined period
The specified delay time, which is set to a sufficiently long time,
Only the electric signal whose upper supply is maintained is output from the fifth terminal.
Will be.

Therefore, the value of the predetermined voltage set in advance by one voltage detecting means is set to, for example, the highest voltage value of the first voltage required to return the electric circuit in the electric equipment to the initial state, that is, a so-called return voltage value. And the dividing ratio of the first voltage into at least one second voltage by the voltage switching means is, for example, the first ratio which can guarantee the normal operation of the electric device.
The comparison operation between the second voltage and the predetermined voltage can be performed by setting a division ratio at which a voltage having a value equal to the above-mentioned return voltage value can be output as the second voltage when the voltage reaches the lowest voltage value, that is, a so-called guaranteed voltage value. Is output as a first confirmation signal for confirming whether or not the voltage value of the first voltage is equal to or lower than the guaranteed voltage value, and an output signal is output by a comparison operation between the first voltage and a predetermined voltage. The signal can be used as a second confirmation signal for confirming whether the voltage value of the first voltage is equal to or less than the return voltage value. That is, in such a case, two types of confirmation outputs having different judgment criteria can be obtained by one voltage detection unit.

[0024]

FIG. 1 is an electric circuit diagram showing an embodiment of a battery check circuit according to the present invention. In FIG. 1, the same reference numerals as those in FIG. 3 indicate the same functional elements.

The voltage switching means 9 connected between the power supply terminal 1 from which the first voltage to be detected is output and the ground,
The first voltage is switched to an appropriate voltage value including the voltage value as it is and supplied to one voltage detection means 14 described later. For example, as shown in FIG. Open-close switch means 1
And control means 13 for controlling the opening and closing operation of
The first terminal 9a, which is the output terminal, is connected to the resistors 10, 11
Are drawn from the connection point.

Therefore, when the on / off switch means 12 performs the opening operation by the control means 13, the first voltage remains unchanged, and when the on / off switch means 12 performs the closing operation, the first voltage is changed to the resistors 10, 1.
One second voltage divided by 1 is output from the first terminal 9a. That is, the present embodiment is an example including the voltage switching unit 9 that outputs one divided voltage obtained by dividing the first voltage by one division ratio set by the resistors 10 and 11 as the second voltage.

The on / off switch means 12 is provided for a predetermined period T1 when it is desired to confirm whether the value of the first voltage is equal to or lower than a guaranteed voltage value which is a minimum voltage value which can guarantee normal operation of the electric equipment.
Is controlled by the control means 13 so as to perform the closing operation.

The control means 13 controls the operation of the open / close switch means 12 in consideration of, for example, a case where it is desired to confirm whether the value of the first voltage is equal to or lower than the guaranteed voltage value.

The open / close switch means 12 is composed of a well-known electric switch such as a transistor or a thyristor. When the open / close switch means 12 is a transistor, the value of the first voltage is a guaranteed voltage. It is configured to output an ON signal for turning on the transistor for a predetermined period T1 based on an appropriate operation that defines a time when it is desired to check whether the value is equal to or less than the value.

One voltage detecting means 14 is connected to the first terminal 9a.
A second terminal 14a as an input terminal and a third terminal 14b as an output terminal, which are electrically connected to the second terminal 14a.
By comparing the voltage supplied to a with a predetermined voltage set in advance, an output signal for performing an inversion operation at the predetermined voltage is output from the third terminal 14b.

For example, the voltage detecting means 14 of the present embodiment
During a predetermined period T1 during which the second voltage is being output, an output signal that is high when the second voltage is higher than the predetermined voltage and low when the second voltage is lower than the predetermined voltage based on a comparison operation between the second voltage and the predetermined voltage. During a period in which the second voltage is not being output, a high level when the first voltage is equal to or higher than the predetermined voltage, and a low level when the first voltage is equal to or lower than the predetermined voltage based on a comparison operation between the first voltage and the predetermined voltage. Is output to the third terminal 14b.
It is configured to output from.

The delay means 15 is constituted by a series body of a resistor 16 and a capacitor 17 connected between the third terminal 14b and the ground. Basically, the delay means 15 includes a resistor 16 electrically connected to the third terminal 14b. The electrical signal supplied to the fourth terminal 15a, which is one end, is delayed from the connection point between the resistor 16 and the capacitor 17 by delaying the electrical signal by a delay time T2 set to a time sufficiently longer than the predetermined period T1. This is output to the terminal 15b. Actually, as mentioned earlier
The state of the third terminal 14b is within the predetermined period T1.
Even if there is a large change, the change appears at the fifth terminal 15b.
The relationship between the delay time T2 and the predetermined period T1 so as not to appear
Is set and supplied to the fourth terminal 15a.
Supply of the electrical signal is maintained for the delay time T2 or more.
Output from the fifth terminal 15b.
You.

The resistor 18 is connected to the power terminal 1 and the third terminal 14b.
It is connected between the (fourth terminal 15a) and controls the potential of the third terminal 14b (fourth terminal 15a) so as not to be in an indefinite state at the start of supply of the power supply voltage, for example.
It should be noted that if the voltage detecting means 14 does not cause the undefined state as described above, it may be omitted.

The value of the predetermined voltage preset in the voltage detecting means 14 in the present embodiment and the division ratio of the first voltage to the second voltage in the voltage switching means 9 are determined by the second voltage in the present embodiment. An output signal output by the comparison operation between the first voltage and the predetermined voltage is used as a first confirmation signal for confirming whether or not the value of the first voltage is equal to or lower than the guaranteed voltage value. In order that the output signal output by the operation can be used as a second confirmation signal for confirming whether or not the value of the first voltage is equal to or lower than the return voltage value, each is set as follows. .

First, the value of the predetermined voltage is set based on the highest voltage value of the first voltage, which is required to return the electric circuit in the electric device to the initial state, that is, the so-called return voltage value.
That is, the return voltage value is set to the lowest level and set to an appropriate voltage value higher than that, for example, a voltage value equal to the return voltage value, and the division ratio is set to the lowest voltage of the first voltage that can guarantee the normal operation of the electric device. The value is set based on a so-called guaranteed voltage value, that is, the above-mentioned guaranteed voltage value is set to the lowest level, and a higher appropriate voltage value, for example, when the voltage value becomes equal to the guaranteed voltage value, the second voltage is set as the second voltage. The division ratio is set so that a voltage having a value equal to the predetermined voltage can be output.

Therefore, assuming that the operation of the electric equipment is started and the value of the first voltage is, for example, a first voltage value equal to or higher than the above-mentioned guaranteed voltage value, the voltage switching means 9 is controlled by the control means 1
3, when the detection switch means 12 is opened in response to the operation of the third switch, the first voltage value is left as it is,
Is closed, the first divided voltage value obtained by dividing the first voltage value is output from the first terminal 9a for a predetermined period T1.

For this reason, the voltage detecting means 14 compares the first voltage value and the first divided voltage value with a predetermined voltage value. Considering that all of the voltage values are equal to or higher than the predetermined voltage value, a high-level output signal is always output from the third terminal 14b, which is the output terminal thereof, regardless of the operation of the open / close switch means 12.

Therefore, the capacitor 17 constituting the delay means 15 is charged through the resistors 18 and 16, and the fifth terminal 15b, one end of which is connected to the connection point between the resistor 16 and the capacitor 17, also has a high level output. It will output a signal.

That is, when the first voltage is the first voltage value, both the first confirmation signal output from the third terminal 14b and the second confirmation signal output from the fifth terminal 15b affect the operation of the open / close switch means 12. Regardless, the voltage state of the power supply where the first voltage is equal to or higher than the guaranteed voltage value can guarantee the normal operation of the electric device and return the electric circuit in the electric device to the initial state. Needless to say, it is not necessary to describe in detail that the first and second confirmation signals are at a high level.
It is possible to recognize that the voltage state of the power supply is proper.

On the other hand, when the first voltage decreases and the voltage value becomes, for example, the second voltage value which is equal to or higher than the previous return voltage value but equal to or lower than the guaranteed voltage value, the voltage switching means 9 controls the control means 13. When the detection switch means 12 is open in response to the operation of the above, the second voltage value is kept as it is and the detection switch means 1
When 2 is closed, a second divided voltage value obtained by dividing the second voltage value is output from the first terminal 9a for a predetermined period T1.

Therefore, when the voltage detecting means 14 compares the second voltage value with the predetermined voltage value from the third terminal 14b, it outputs a high-level output signal as in the previous case. During the period T1, when the second divided voltage value is compared with the predetermined voltage value, in consideration of the above-described setting conditions of the division ratio, the state where the high-level output signal was output is inverted to perform the low-level operation. Will be output.

Therefore, the fifth terminal 15b of the delay means 15
The high-level or low-level output signal output from the third terminal 14b is likely to be output after the delay time T2, but as described above, the delay time T2 is equal to the predetermined time T2.
1, the low-level output signal is a signal that is output only during the predetermined period T1. Therefore, in such a case, the third terminal 14
The low-level signal b is not delayed and output,
As in the previous case, a high-level output signal is always output to the fifth terminal 15b of the delay means 15.

That is, when the first voltage becomes the second voltage value, the first confirmation signal output from the third terminal 14b is inverted to a high or low level in response to the operation of the open / close switch means 12. The second confirmation signal output from the fifth terminal 15b is always maintained at a high level irrespective of the operation of the open / close switch means 13, while the voltage state of the power supply in which the first voltage becomes the second voltage value It is needless to say in detail that the normal operation of the electric device cannot be guaranteed but the operation of returning the electric circuit in the electric device to the initial state is not necessary. By confirming the inversion operation, the voltage state of the power supply is in a state in which the normal operation of the electric device cannot be guaranteed, and by confirming that the second confirmation signal is at a high level, the voltage state of the power supply is determined by the electric circuit in the electric device. initial It recognizes that it is a state that does not require a return operation to the state.

For example, by operating some notification means by a first confirmation signal inverted to a low level,
The user of the electric device can recognize that the voltage state of the power supply is equal to or lower than the guaranteed voltage value.

When the first voltage further decreases to a third voltage value equal to or lower than the return voltage value, the voltage switching means 9 responds to the operation of the control means 13 when the detection switch means 12 is opened. 3 as the detection switch means 1
When 2 is closed, a third divided voltage value obtained by dividing the third voltage value is output from the first terminal 9a for a predetermined period T1.

Therefore, the voltage detection means 14
And the third divided voltage value are compared with the predetermined voltage value. In this case, considering that the above-mentioned setting conditions of the division ratio are all less than the predetermined voltage value, the output terminal Irrespective of the operation of the open / close switch means 12, a low-level output signal is always output from the third terminal 14b from the moment when the first voltage becomes equal to or lower than the reset voltage value.

For this reason, the charge of the capacitor 17 constituting the delay means 15 that has been charged up to that point is transferred to the resistor 16.
Through the delay time T2, the fifth terminal 15b inverts after the delay time T2 elapses, and outputs a low-level output signal. Exchange
In other words, a third voltage in which the first voltage is equal to or lower than the return voltage value
And a low level output signal is always output from the third terminal 14b.
Output means that the signal is output from the third terminal 14b.
Terminal 15 of the electric signal (the low-level output signal)
a is maintained for the delay time T2 or more.
As a result, the delay means 15 has the predetermined delay
After the elapse of the extension time T2, the fourth terminal 15 is moved from the fifth terminal 15b.
a low-level electrical signal being an electrical signal being supplied to a
Will be output.

That is, when the first voltage becomes the third voltage value, the first confirmation signal output from the third terminal 14b performs an inversion operation to a low level regardless of the operation of the open / close switch means 12, and The second confirmation signal output from the fifth terminal 15b also inverts to a low level after the elapse of the delay time T2. On the other hand, the voltage state of the power supply in which the first voltage is the third voltage value is the same as that of the electric device. It is needless to say that the normal operation cannot be guaranteed and the electric circuit in the electric device also needs to return to the initial state. This results in the low level of the first and second confirmation signals. By confirming the reversal operation, it is possible to recognize that the voltage state of the power supply is a state in which the normal operation of the electric device cannot be guaranteed, and that the electric circuit in the electric device needs to return to the initial state.

For example, it is possible to use the second confirmation signal as a so-called reset signal by returning the electric circuit in the electric device to the initial state by the second confirmation signal inverted to the low level. By operating some notification means by the first and second confirmation signals, it is possible to make the user of the electric device recognize that the voltage state of the power supply is equal to or lower than the guaranteed voltage value and equal to or lower than the return voltage value.

FIG. 2 is an electric circuit diagram showing another embodiment of the battery check circuit according to the present invention. In FIG. 2, the same reference numerals as those in FIG. 1 indicate the same functional elements.

As is apparent from FIG. 2, this embodiment differs from the embodiment shown in FIG. 1 only in the configuration of the voltage switching means 9.

That is, the voltage switching means 9 of this embodiment is
This is an example in which the first voltage can be divided at a plurality of division ratios, and the first voltage is supplied to one voltage detecting means 14 by switching to a plurality of divided voltage values including the voltage value as it is. , A resistor 19 and a resistor 2 between the power terminal 1 and the ground.
A connection formed by serially connecting a first series body in which 0 and the first on / off switch means 21 are connected in series and a parallel connection body 24 consisting of a second series body in which the resistor 22 and the second on / off switch means 23 are connected in series. Body and first and second on / off switch means 2
The first terminal 9a is drawn out from a connection point between the resistor 19 and the parallel connection body 24.

Therefore, three kinds of division ratios can be selectively set by opening / closing control of the first and second opening / closing switch means 21 and 23 based on the operation of the control means 25. For example, when only the first on / off switch 21 is operated to close, the first voltage is divided by the resistors 19 and 20 to generate a first second voltage. When only the second on / off switch 23 is operated to close, the first voltage is applied. A second second voltage obtained by dividing the voltage by the resistors 19 and 22 is further divided into first and second on / off switch means 21 and
When both of them are closed, the first voltage is changed to the resistance 19,
The third second voltages divided at 20 and 22 can be output from the first terminal 9a. That is, in the embodiment of FIG. 2, the first voltage is set to the resistor 19 and the resistor 2 as the second voltage.
This is an example provided with voltage switching means 9 that can output up to three divided voltages divided by up to three division ratios set by a combination of 0 and 22.

The first and second on / off switch means 21,
23 is a well-known electric switch such as a transistor or a thyristor, as in the previous embodiment. The control means 25 controls the operation of the first and second on / off switch means 21 and 23 by, for example, a first voltage. Is controlled for a predetermined period T1 based on an appropriate operation for defining a time when it is desired to confirm whether the value is equal to or lower than the guaranteed voltage value, and the configuration of the other voltage detecting means 14 and the like is shown in FIG. It has the same configuration as the embodiment shown.

Since the embodiment shown in FIG. 2 has the above-described configuration, the value of the predetermined voltage preset in the voltage detecting means 14 is set to a so-called return voltage value, as in the previous embodiment. Further, by setting the division ratio in the voltage switching means 9 capable of setting up to three division ratios to, for example, the following two division ratios, the following development can be considered.

That is, based on a so-called guaranteed voltage value, for example, when one of the two division ratios becomes the guaranteed voltage value, a voltage having a value equal to the predetermined voltage value is output as the second voltage. The other one of the possible first division ratios has a so-called warning voltage value, for example, in which the first voltage is higher than or equal to the guaranteed voltage value, but drops to the vicinity thereof, and it can be regarded that it is necessary to instruct preparation for power supply replacement. In some cases, the second voltage is set to a second division ratio capable of outputting a voltage having a value equal to the value of the predetermined voltage, so that the two second voltages obtained through the first and second division ratios and the predetermined voltage are different from each other. The output signal output by the comparison operation is changed, for example, by prohibiting the operation of the device by confirming whether or not the value of the first voltage is equal to or lower than the guaranteed voltage value, or by replacing the power supply by confirming whether or not the value has dropped to around the guaranteed voltage value. Make a preparation announcement In order to perform a reset operation by confirming whether or not the value of the first voltage is equal to or less than the reset voltage value, the output signal output by the comparison operation between the first voltage and the predetermined voltage is used as the first confirmation signal for Can be used as the second confirmation signal.

Therefore, assuming that the operation of the electric equipment is now started and the value of the first voltage is, for example, a fourth voltage value equal to or higher than the above-mentioned warning voltage value, the voltage switching means 9 is controlled by the control means 2
5 based on the operation of the first and second detection switch means 21 and 2
By the operation of 3, the fourth voltage value is not changed, or the second voltage obtained by dividing the fourth voltage value by the first and second division ratios, that is, the two divided voltage values is supplied to the first terminal for a predetermined period T1. 9a.

For this reason, the voltage detecting means 14 compares the fourth voltage value and the two divided voltage values with the predetermined voltage value. In this case, it is considered from the above-described setting conditions of the division ratio. Since any voltage value becomes equal to or higher than the predetermined voltage value, a high-level output signal is always output from the third terminal 14b, which is the output terminal thereof, regardless of the operation of the first and second on / off switch means 21 and 23. That is, similarly to the previous embodiment, the fifth terminal 15b of the delay means 15 always outputs a high-level output signal.

That is, when the first voltage is the fourth voltage value, both the first and second confirmation signals output from the third terminal 14b and the fifth terminal 15b are the first and second on / off switch means 21 and 23. Regardless of the operation, the signal is always at a high level. On the other hand, the voltage state of the power supply in which the first voltage is equal to or higher than the warning voltage value does not require the preparation notification such as battery replacement and can guarantee the normal operation of the electric device, and It is needless to say in detail that the electric circuit in the electric device does not require the return operation to the initial state, and as a result, it is confirmed that the first and second confirmation signals are at the high level. It can be recognized that the voltage state is appropriate.

On the other hand, when the first voltage decreases and the voltage value becomes, for example, a fifth voltage value that is equal to or higher than the above-mentioned guaranteed voltage value but equal to or lower than the warning voltage value, the voltage switching unit 9 operates similarly to the previous case. By the operation of the first and second detection switch means 21 and 23, the fifth voltage value is unchanged or two divided voltage values obtained by dividing the fifth voltage value by the first and second division ratios over a predetermined period T1. The signal is output from the first terminal 9a.

Therefore, the voltage detecting means 14 has its third
When the fifth voltage value is compared with the predetermined voltage value from the terminal 14b, a high-level output signal is output.
When comparing the two divided voltage values with the predetermined voltage value during the predetermined period T1, one of the two divided voltage values becomes lower than the predetermined voltage value in consideration of the above-described setting conditions of the division ratio. At this time, the inversion operation is performed from the state where the high-level output signal was output, and the low-level output signal is output from the third terminal 14b.

The high or low level output signal output from the third terminal 14b is supplied to the fourth terminal 15a of the delay means 15, and the relationship between the delay time T2 and the predetermined period T1 and the low level output signal Because of the output period, a high-level output signal is always output to the fifth terminal 15b of the delay unit 15 as in the previous case.

That is, when the first voltage reaches the fifth voltage value, two signals, a signal maintained at a high level and a signal for performing an inversion operation at a high or low level, are used as a third confirmation signal as a third confirmation signal. The second confirmation signal output from the terminal 14b and output from the fifth terminal 15b is always maintained at a high level,
On the other hand, in the voltage state of the power supply in which the first voltage has reached the fifth voltage value, the normal operation of the electric device can be guaranteed, but it is necessary to prepare for notification such as battery replacement, and the initial state of the electric circuit in the electric device. It is needless to mention that the operation of returning to the state is not required, so it is necessary to prepare for the notification of battery replacement by confirming the signal for performing the inversion operation to the low level among the first confirmation signals. By confirming that the second confirmation signal is at a high level, it is possible to recognize that the electric circuit in the electric device does not need to return to the initial state.

For example, by operating some notification means by a first confirmation signal inverted to a low level,
The user of the electric apparatus can be made aware that the voltage state of the power supply is a state in which preparation for replacement or the like is necessary.

When the first voltage further decreases and reaches the sixth voltage value equal to or lower than the guaranteed voltage value, the voltage switching means 9 operates the first and second detection switch means 21 and 23 to operate the sixth voltage value. , Or two divided voltage values obtained by dividing the sixth voltage value by the first and second division ratios are output from the first terminal 9a over a predetermined period T1.

Therefore, the voltage detecting means 14 has its third
When the sixth voltage value is compared with the predetermined voltage value from the terminal 14b, a high-level output signal is output.
When the two divided voltage values are compared with the predetermined voltage value during the predetermined period T1, the two divided voltage values are lower than the predetermined voltage value in consideration of the above-described setting conditions of the division ratio. The inversion operation is performed from a state other than the predetermined period T1 during which the output signal was output, and a low-level output signal is output from the third terminal 14b.

The low-level output signal output from the third terminal 14b is supplied to the fourth terminal 15a of the delay means 15, and the relationship between the delay time T2 and the predetermined period T1 and the output period of the low-level output signal Therefore, a high-level output signal is always output to the fifth terminal 15b of the delay unit 15 as in the case described above.

That is, when the first voltage has reached the sixth voltage value, the first confirmation signal output from the third terminal 14b has a low level regardless of the operation of the first and second on / off switch means 21 and 23. And the second confirmation signal output from the fifth terminal 15b is always maintained at a high level.
On the other hand, the above-described voltage state of the power supply in which the first voltage is the sixth voltage value is a state in which normal operation of the electric device cannot be guaranteed, but a return operation of the electric circuit in the electric device to the initial state is not required. As a result, it is needless to say that as a result, it is confirmed that the voltage state of the power supply is in a state where the normal operation of the electric device cannot be guaranteed by confirming the inversion operation of the first confirmation signal to a low level, and the second confirmation. By confirming that the signal is at a high level, it is possible to recognize that the electric circuit in the electric device is in a state that does not require a return operation to the initial state.

When the first voltage further decreases to a seventh voltage value equal to or lower than the return voltage value, the voltage switching means 9 operates the first and second detection switch means 21 and 23 to operate the seventh voltage value as in the previous case. , Or two divided voltage values obtained by dividing the seventh voltage value by the first and second division ratios are output from the first terminal 9a over a predetermined period T1.

Therefore, the voltage detection means 14
And the two divided voltage values are compared with the predetermined voltage value.In this case, considering both of the above-described setting conditions of the division ratio, the voltage value is equal to or less than the predetermined voltage value. From a certain third terminal 14b, regardless of the operation of the first and second on / off switch means 21 and 23, a low-level output signal is always output from the moment when the first voltage reaches the seventh voltage value equal to or lower than the reset voltage value. Output.

For this reason, the charge of the capacitor 17 constituting the delay means 15 that has been charged up to that point is transferred to the resistor 16.
It would be discharged over the previous delay time T2 through, when similarly fifth terminal 15b of the previously inverted operation after elapse of the delay time T2, will output a low level of the output signal.

That is, when the first voltage becomes the seventh voltage value, the first confirmation signal output from the third terminal 14b performs an inversion operation to a low level, and thus the first confirmation signal output from the fifth terminal 15b. The second confirmation signal also inverts to a low level after the elapse of the delay time T2. On the other hand, the voltage state of the power supply in which the first voltage is the seventh voltage value cannot guarantee normal operation of the electric device, and It is needless to say that it is a state that also requires a return operation to the initial state of the electric circuit in the power supply. As a result, the power supply of the power supply is confirmed by confirming the inversion operation of the first and second confirmation signals to a low level. It can be recognized that the voltage state is a state in which the normal operation of the electric device cannot be guaranteed, and that the electric circuit in the electric device requires a return operation to the initial state.

For example, it is possible to use the second confirmation signal as a so-called reset signal by returning the electric circuit in the electric device to the initial state by the second confirmation signal inverted to the low level. By operating some notification means by the first and second confirmation signals, it is possible to make the user of the electric device recognize that the voltage state of the power supply is equal to or lower than the guaranteed voltage value and equal to or lower than the return voltage value.

As described above, in the embodiment shown in FIG. 2 in which the series body composed of the combination of the resistor and the open / close switch is connected in parallel, it is possible to detect at least four kinds of power supply voltage states by one voltage detector. become.

Although not shown, it is also possible to connect a larger number of series members composed of a combination of a resistor and an open / close switch in parallel.

[0076]

According to the battery check circuit of the present invention,
Voltage switching means for selectively outputting at least two kinds of detection voltages, and one voltage detection means for comparing the detection voltage with a predetermined voltage set in advance based on a so-called return voltage value; Since two selective comparison results obtained by the comparison operation by the voltage detection means are output directly and via the delay means, one voltage detection means detects the voltage state of at least three power supplies. ,
For example, a so-called battery check operation that detects whether the voltage state of the power supply is a state that can guarantee the normal operation of the electric device, and a state in which the voltage state of the power supply needs to return the electric circuit in the electric device to the initial state. A reset operation for detecting whether or not this is the case can be performed, which has the effect of reducing the cost of the entire electric device.

[Brief description of the drawings]

FIG. 1 is an electric circuit diagram showing an embodiment of a battery check circuit according to the present invention.

FIG. 2 is an electric circuit diagram showing another embodiment of the battery check circuit according to the present invention.

FIG. 3 is an electric circuit diagram illustrating a main part of an example of a conventionally known electric device including a battery check circuit and a reset circuit.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 power supply terminal 2 battery check circuit 3 first voltage detecting means 4 detection switch 5 resistor 6 reset circuit 7 second voltage detecting means 8 resistor 9 voltage switching means 10 resistor 11 resistor 12 on / off switch means 13 control means 14 voltage detecting means 15 delay Means 16 Resistance 17 Capacitor 18 Resistance 19 Resistance 20 Resistance 21 First open / close switch means 22 Resistance 23 Second open / close switch means 24 Parallel connection 25 Control means

Claims (6)

(57) [Claims] 1. A battery check circuit comprising a voltage switching means, a voltage detection means, and a delay means, wherein the voltage switching means has a first terminal and outputs a first voltage to be detected. The power supply terminal is connected between the power supply terminal and the ground, and outputs the first voltage at all times from the first terminal and at least one second voltage obtained by dividing the first voltage during the selected predetermined period. It has a second terminal and a third terminal, and outputs an output signal for performing an inversion operation at a predetermined voltage from the third terminal by comparing a voltage supplied to the second terminal with a predetermined voltage. , The delay means has a fourth terminal and a fifth terminal, and the electric power supplied to the fourth terminal
An electrical signal whose supply is maintained for a predetermined delay time
Only the signal is output from the fifth terminal, the first terminal is electrically connected to the second terminal, and the third terminal is electrically connected to the fourth terminal, and the predetermined delay time is set to a time sufficiently longer than the predetermined period. A signal output from the third terminal during a predetermined period in which the second voltage is output is set as a first confirmation signal for confirming the state of the first voltage, and a signal output from the fifth terminal is used as the first voltage. A battery check circuit that outputs a second check signal for checking the state of the battery. 2. The voltage switching means comprises a series body comprising a plurality of resistors and on / off switch means, a control means, and a first terminal. The control means is provided when the state of the first voltage is to be checked. Wherein the first terminal has one end connected to a connection point of the plurality of resistors and outputs a first voltage when the on / off switch means is in an open operation and a second voltage when the on / off switch is in a closed operation. A battery check circuit as described. 3. The battery check circuit according to claim 2, wherein the on / off switch means comprises an electric switch such as a transistor or a thyristor. 4. The voltage switching means comprises: a series connection body formed by connecting a resistor in series with a parallel connection body formed by connecting a plurality of series bodies each comprising a resistor and an on / off switch means in parallel; , A first terminal, wherein the control means selectively closes a plurality of on / off switch means of the parallel-connected body for a predetermined period when it is desired to check the state of the first voltage, and the first terminal is connected to the parallel-connected body. 2. The battery check circuit according to claim 1, wherein one end is connected to a connection point with the resistor, and the first voltage is output when a plurality of on / off switch means are opened and the plurality of second voltages are output when a selective closing operation is performed. 5. The battery check circuit according to claim 4, wherein the open / close switch means comprises an electric switch such as a transistor or a thyristor. 6. The delay means comprises a series body of a resistor and a capacitor connected between a third terminal and the ground. One end of a resistor not connected to the capacitor has a fourth terminal, and the other end connected to the capacitor has a fifth terminal. 2. The battery check circuit according to claim 1, wherein a terminal is formed.