JPH11237934A - Auxiliary power unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an auxiliary power unit which can prolong the lifetime of a backup battery and also can eliminate a complicated battery attachment job for its user. SOLUTION: This power unit is reset when a main power supply 101 is cut and the output of a backup battery 102 is supplied for an RS flip-flop consisting of two NAND gates 112 and 113 and then set when the outputs of both battery 102 and supply 101 are supplied. When the RS flip-flop is reset by an FET 114, the output of the battery 102 is not supplied to an object device 104. Then the output of the battery 102 is supplied to the device 104 when the RS flip-flop is set.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an NC, a robot,
Alternatively, in an information processing apparatus such as a computer, the present invention relates to an auxiliary power supply apparatus for backing up a power supply to a volatile memory or a CPU in the apparatus when a main power supply is shut off.
During storage from the end of product testing to shipment, the auxiliary power supply itself is disabled to prevent the backup battery from being exhausted, and the auxiliary power supply is enabled after the user turns on the main power supply to back up the power of the target device. By doing so, the present invention relates to an auxiliary power supply device that extends the life of a backup battery and does not require a complicated battery mounting operation by a user.

[0002]

2. Description of the Related Art As a conventional auxiliary power supply (hereinafter referred to as a conventional example), for example, there is one as shown in FIG. This conventional example is disclosed in Japanese Patent Application Laid-Open No. Hei 1-107626. When the main power supply is turned off, the consumption of a backup power supply for retaining the storage contents of a memory in the device is delayed, and replacement of a battery is performed. The number of times is reduced. FIG.
FIG. 1 is a configuration diagram of a backup power supply circuit of the conventional example.
In the figure, reference numeral 104 denotes a device including a volatile memory such as an SRAM that needs to back up power when the main power supply 301 is in a cut-off state. This target device 10
4, a main power supply 301 having a voltage Vcc, a backup battery 302 having a voltage Vba, and a backup capacitor 303 having a charging voltage Vc are connected in parallel via backflow preventing diodes D1 to D4, respectively. Where 3
The magnitude relationship between the voltages Vcc, Vba and Vc is such that the voltages Vcc and Vc are substantially the same, and the voltages Vc and Vba are Vc
> Vba. For example, Vcc = Vc = 5
At [V], Vba is set to 3.6 [V]. Main power supply 30
When 1 is in the ON state, power is supplied from the main power supply 301 to the target device 104 via the diode D1, and the volatile memory such as the SRAM in the target device 104 operates normally. At this time, the backup capacitor 303
Is also charged to the voltage Vc via the diode D3. Eventually, when the operator turns off the main power supply 301, while the charging voltage Vc of the backup capacitor 303 is higher than the voltage Vba of the backup battery 302, the electric charge charged in the backup capacitor 303 passes through the diode D. Since the target device 104 is backed up by discharging, the operation state of the SRAM or the like is maintained. Further, the backup battery 302 does not need to be consumed by that much. Further, when the charging voltage Vc becomes equal to or lower than the voltage Vba of the backup battery 302 due to discharging,
Power is backed up from the backup battery 302 to the target device 104 via the diode D2.

[0003]

As described above, the conventional auxiliary power supply has a configuration in which the backup battery 302 and the backup large-capacity capacitor 303 are connected in parallel with the main power supply 301 and used. Although industrial equipment such as NCs and robots are energized every day, backup by the backup capacitor 303 is usually sufficient, and the backup battery 302 is consumed only on long holidays. In an information processing device such as an NC, a robot, or a computer,
If the time from the end of the test to the shipment of the product is long, the electric charge of the backup capacitor 303 connected in parallel will be completely discharged during storage, so that the backup battery 30
2, the backup of the backup battery 302 is severe, and the capacity of the backup battery 302 depends on the storage time. As a measure for avoiding such consumption of the backup battery 302, the backup battery 302 is removed after the test is completed, and the backup battery 30
Although it is conceivable that the user attaches the mounting member 2, the user is required to perform a complicated mounting operation, and an undesirable situation has occurred. SUMMARY OF THE INVENTION The present invention has been made in view of the above-described conventional problems, and during storage from the end of a product test to the shipment, the auxiliary power supply itself is disabled to prevent consumption of a backup battery. By enabling the auxiliary power supply to perform power backup of the target device after the main power supply is turned on,
It is an object of the present invention to provide an auxiliary power supply device that extends the life of a backup battery and does not require a complicated battery mounting operation by a user.

[0004]

In order to solve the above problems, an auxiliary power supply according to a first aspect of the present invention is driven by a backup power supply connected in parallel to a main power supply and the backup power supply. State information holding means for holding state information according to the output of the main power supply and the output of the backup power supply, and opening and closing according to the contents of the state information holding means, supplying the output of the backup power supply to a load And switching means for controlling The auxiliary power supply according to claim 2 is
2. The auxiliary power supply device according to claim 1, wherein the backup power supply includes a battery and a capacitor respectively connected in parallel to the main power supply. 3. Furthermore, the auxiliary power supply device according to claim 3 is the auxiliary power supply device according to claim 1 or 2.
3. The auxiliary power supply device according to claim 1, wherein the state information holding unit holds the first state when the main power supply output is equal to or lower than a first potential and the backup power supply output exceeds a second potential. When the output exceeds the second potential and the main power supply output exceeds the first potential, the second state is held, and the switching unit is configured to switch the state when the state information holding unit holds the first state. The backup power supply output is not supplied to the load, and the backup power supply output is supplied to the load when the state information holding unit holds the second state.

In the auxiliary power supply according to the first and second aspects of the present invention, the state information holding means driven by the backup power supply connected in parallel with the main power supply outputs the output of the main power supply and the backup power supply. Since the state information corresponding to the output is held and the switching means is opened and closed according to the contents of the state information holding means to control the supply of the output of the backup power supply to the load, for example, from the end of the product test to the shipment. During storage, the auxiliary power supply itself is disabled to prevent consumption of the backup power supply, and after the main power supply is turned on by the user, the auxiliary power supply is enabled and the power of the target device is controlled by the auxiliary power supply. Since backup can be performed, the life of the backup power source is extended, and It is possible to eliminate the need for cumbersome battery installation work of. In particular, in the auxiliary power supply device according to claim 3, the state information holding means holds the first state when the main power supply output is lower than the first potential and the backup power supply output exceeds the second potential. When the output exceeds the second potential and the main power supply output exceeds the first potential, the second state is held, and when the state information holding means holds the first state, the backup power supply output is output. Is not supplied to the load, and when the state information holding means holds the second state, the backup power supply output is supplied to the load. Therefore, during storage from the end of the test of the product to shipment, the state information holding means is in the first state. To prevent backup power consumption, and
After the user turns on the main power supply, the state information holding unit can hold the second state and perform power backup of the target device by the auxiliary power supply device. As a result, the life of the backup power supply can be extended and This eliminates the need for the user to perform a complicated battery mounting operation.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the auxiliary power supply according to the present invention will be described below in detail with reference to the drawings. FIG. 1 is a configuration diagram of an auxiliary power supply device according to an embodiment of the present invention. In the figure, the same reference numerals are given to portions overlapping with FIG. 3 (conventional example). The auxiliary power supply of this embodiment is
In an information processing apparatus such as an NC, a robot, or a computer, power supply to a target device 104 such as a volatile memory or a CPU in the apparatus is backed up when a main power supply is cut off. In FIG. 1, an auxiliary power supply according to the present embodiment includes a main power supply 101 as a backup power supply connected in parallel to a main power supply 101 having an output voltage Vcc.
A backup battery 102 of the output voltage Vba and a large-capacity capacitor (capacitor) 103 of the charging voltage Vc, which are connected in parallel to each other. The resistor R1 and the capacitor C1, and the NAND gates 111 to 1
13. p-channel field-effect transistor (hereinafter referred to as FE)
T) 114 and a backflow preventing diode D2
To D4. The magnitude relationship between the three types of voltages Vcc, Vba and Vc is such that the voltages Vcc and Vc are substantially the same, and the voltages Vc and Vba satisfy Vc> Vba. For example, if Vcc = Vc = 5 [V] and Vba
= 3.6 [V]. Further, the backup capacitor 103 is of the order of 1 [F], so that a backup of usually about 3 days is possible.

The resistor R1 and the capacitor C1 are connected in series between the output terminal of the backup battery 102 and ground,
From a connection node between the resistor R1 and the capacitor C1, a reset signal RES # indicating whether or not the output voltage Vba of the backup battery 102 exists is generated. In addition, from the NAND gate 111 driven by the backup battery 102 (voltage Vba), an RS-flip-flop set signal SET # indicating whether or not the output voltage Vcc of the main power supply 101 is present.
Is output. In this specification, the symbol # added at the end of a signal name indicates that the signal is a negative logic signal. The state information holding means for holding state information according to the output voltage Vcc of the main power supply 101 and the output voltage Vba of the backup battery 102 is driven by the backup battery 102 (voltage Vba).
This is realized by an RS flip-flop including the NAND gates 112 and 113. The output signal G of the RS flip-flop reflects the state information, and becomes “H” when the output voltage Vcc of the main power supply 101 becomes “L” level and the output voltage Vba of the backup battery 102 becomes “H” level. Level, and when the output voltage Vba of the backup battery 102 is at “H” level, the main power supply 1
01 when the output voltage Vcc becomes "H" level.
L ”level. The three NAND gates 1
Reference numerals 11 to 113 are realized by MSI or the like having the Schmitt function of the 74HC132. Further, a switching unit that opens and closes in response to the output signal G of the RS flip-flop and controls the power supply of the backup battery 102 to the target device 104 is realized by the FET 114, and the output signal G of the RS flip-flop is realized. Is turned on when the output voltage is lower than the output voltage Vba of the backup battery 102, and is turned off when the output voltage Vba is exceeded. The output voltage Vba of the backup battery 102
Is connected to the charging voltage Vc of the backup capacitor via the FET 114 and the diode D2 and is wired-ORed to provide the supply voltage to the target device 104.

Next, the operation of the auxiliary power supply device according to the present embodiment having the above configuration will be described with reference to the timing chart of each voltage and signal shown in FIG. 2A shows the output voltage Vcc of the main power supply 101, FIG. 2B shows the output voltage Vba of the backup battery 102, and FIG. 2C shows the presence or absence of the output voltage Vba of the backup battery 102. A reset signal RES # of the RS-flip-flop, FIG. 2D shows an output signal G of the RS-flip-flop holding state information, and FIG. 2E shows an RS-flip indicating whether or not the output voltage Vcc of the main power supply 101 is present. FIG. 6 is a voltage waveform diagram showing a set signal SET # of the pump.

First, at timing TA, the main power supply 1
01 is shut off, the output voltage Vcc is not supplied, and the backup battery 102 is also removed to remove the output voltage Vba.
Is in the “L” level state. Next, at timing TB
When the backup battery 102 is connected, the output voltage Vba of the backup battery 102 rises to "H" level as shown in FIG. As a result, the set signal SET # becomes "H" level as shown in FIG. 2 (e), and the reset signal RES # gradually rises with a time constant of R1.times.C1 as shown in FIG. 2 (c). , RS-flip-flop, the output signal G of the RS-flip-flop goes high. That is, the output signal G of the RS flip-flop is “H”.
Level, the FET 114 is turned off, and after the backup capacitor 103 is discharged, the output voltage Vba of the backup battery 102 is
Is no longer supplied to the target device 104, and when the product is in a storage state from the end of the test to the shipment, the consumption of the battery capacity of the backup battery 102 becomes three N
Only the driving of the AND gates 111 to 113 is limited, and the consumption of the battery capacity can be suppressed. Next, when the main power supply 101 is connected by the user at the timing TC, the set signal SET # becomes "L" level as shown in FIG. 2 (e), so that the RS-flip-flop sets the state information, The output signal G of the RS-flip-flop goes to "L" level. That is, when the output signal G of the RS-flip-flop goes to the “L” level, the FET 114 is turned on, whereby the charging voltage Vc is used as a backup power supply connected in parallel to the main power supply 101 having the output voltage Vcc. Together with the backup capacitor 103, the backup battery 102 having the output voltage Vba can be used. Note that the reset signal RE
Since S # remains at the "H" level as shown in FIG. 2C, the main power supply 101 is cut off and the output voltage Vcc is output.
Is at the "L" level, the state information of the RS-flip-flop is retained, and the FET 114 remains on by the output signal G of the RS-flip-flop.

As described above, in the power supply auxiliary device of the present embodiment, in the RS-flip-flop including the two NAND gates 112 and 113, the main power supply 101 is cut off and the output of the backup battery 102 is output. Is reset when the power supply is supplied, and is set when the output of the backup battery 102 is supplied and the output of the main power supply 101 is supplied. When the flip-flop is reset, the output of the backup battery 102 is not supplied to the target device 104, and when the RS-flip-flop is set, the output of the backup battery 102 is supplied to the target device 104. RS-flip-flop is reset during storage from to shipment In addition, the backup battery 102 can be prevented from being consumed, and after the user turns on the main power supply 101, the RS-flip-flop is set and the backup battery 102 performs power backup of the target device 104. As a result, it is possible to extend the life of the backup battery 102 and eliminate the need for the user to perform a complicated battery mounting operation.

[0011]

As described above, according to the auxiliary power supply of the present invention, the output of the main power supply and the backup power supply are provided in the state information holding means driven by the backup power supply connected in parallel with the main power supply. Since the state information corresponding to the output of the power supply is held, and the switching means is opened and closed according to the contents of the state information holding means to control the supply of the output of the backup power supply to the load. During storage until the auxiliary power supply itself is disabled, the backup power supply can be prevented from being consumed, and after the main power supply is turned on by the user, the auxiliary power supply is enabled to enable the auxiliary power supply to operate the target device. Power backup can be performed, and as a result, the life of the backup power It is possible to provide an auxiliary power supply device which can eliminate the need for coarse battery installation work. Further, according to the auxiliary power supply device of the present invention, in the state information holding means,
The first state is maintained when the main power supply output is lower than the first potential and the backup power supply output exceeds the second potential, and the backup power supply output exceeds the second potential and the main power supply output exceeds the first potential. The second state is held when the state information is held.
When the state is held, the backup power supply output is not supplied to the load, and when the state information holding means holds the second state, the backup power supply output is supplied to the load.
During storage from the end of the test of the product to shipment, the state information holding means holds the first state to prevent the backup power supply from being consumed, and after the user turns on the main power supply, the state information holding means stores the first state. An auxiliary power supply device that can perform power backup of a target device by the auxiliary power supply device while maintaining the second state, thereby extending the life of the backup power supply and eliminating the need for a user to perform complicated battery installation work. Can be provided.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an auxiliary power supply device according to an embodiment of the present invention.

FIG. 2 is a timing chart showing voltage waveforms of respective voltages and signals in the auxiliary power supply device of the embodiment.

FIG. 3 is a configuration diagram of a conventional auxiliary power supply device.

[Explanation of symbols]

REFERENCE SIGNS LIST 101 Main power supply 102 Backup battery 103 Backup capacitor (capacitor) 104 Target device 111-113 NAND gate 112, 113 RS flip-flop 114 p-channel type field effect transistor (FE)
T) (switching means) 113 R1 resistor C1 capacitor D1 to D4 diode for preventing backflow Vcc output voltage of main power supply Vba output voltage of backup battery Vc charging voltage of backup capacitor RES # reset signal SET # set signal G RS flip-flop Output signal

Claims (3)

[Claims] 1. A backup power supply connected in parallel to a main power supply, and state information holding means driven by the backup power supply and holding state information corresponding to an output of the main power supply and an output of the backup power supply. And a switching unit that opens and closes according to the contents of the state information holding unit and controls supply of the output of the backup power supply to the load. 2. The auxiliary power supply device according to claim 1, wherein the backup power supply has a battery and a capacitor connected in parallel to the main power supply, respectively. 3. The state information holding means holds a first state when the main power supply output is equal to or lower than a first potential and the backup power supply output exceeds a second potential. The second state is maintained when the output exceeds the second potential and the output of the main power supply exceeds the first potential, and the switching means is used for the backup when the state information holding means holds the first state. 3. The auxiliary power supply according to claim 1, wherein the power supply output is not supplied to the load, and the backup power supply output is supplied to the load when the state information holding unit holds the second state. 4. apparatus.