JPS62216018A - Battery backup system - Google Patents

Abstract

PURPOSE:To easily check the output voltage of a battery through a simple circuit constitution by performing the check of said output voltage at a rise time point of a power supply part. CONSTITUTION:When a power supply part 1 is turned on, the output voltage of the part 1 reaches the rise voltage level and a power supply monitor part 3 turns on the detection signal (2) to set a changeover switch part 5 under a short state for supply of voltage to a memory 2. While a switch part 13 is also set under a short state to impress the output voltage of a battery 4 to a load resistor F. Then a comparison part 14 compares the output voltage of the battery 4 with the reference voltage level. When the output voltage of the battery 4 is lower than the prescribed level, the part 4 decides the abnormality of the battery 4 and sends the abnormality signal to a signal recognizing part 21 for display of the battery abnormality.

Description

[Detailed Description of the Invention] (Summary) This is a battery backup method that uses a battery to back up the holding voltage for the memory when the voltage supply from the power supply section is cut off. When starting, before starting charging from the power supply unit, check the output voltage of the battery with the load connected, and after the check is completed, configure the battery to charge with the supply voltage from the power supply unit. It is possible to grasp the output voltage state of the battery with a simple circuit configuration, and it is also possible to grasp the authenticity of the memory storage data held by the output voltage of the battery.

[Industrial application field]

The present invention relates to a backup method when voltage supply from a power supply section is cut off, and particularly to a battery backup method in which a battery backs up the voltage held in a memory.

For example, volatile memory (eg, CMO5RAM, etc.) is generally used as an information storage unit used in various terminal devices connected to a data processing system.

If the power supply voltage is cut off while this volatile memory is in use, the stored information becomes unusable, so a backup battery is required to retain the stored information during the power supply cutoff period. shall be.

However, if the backup battery does not provide backup at a specified voltage, the information stored in the volatile memory becomes unreliable.

The practical application of a system that can check for abnormalities in such backup batteries with a simple circuit configuration is awaited.

[Conventional technology]

FIG. 3 is a block diagram illustrating a conventional example, and FIG. 4 is a diagram illustrating a power supply voltage monitoring situation.

The block diagram in FIG. 3 shows related blocks that supply voltage from a simple power supply section 1 to a memory (RAM) 2, which is installed in a terminal device for data processing, and its configuration is as follows: Each functional block inside the terminal device A power supply unit 1 that supplies power for operation of the terminal device, a memory (RAM) 2 that stores information that can be rewritten and is processed within the terminal device, and a power supply monitor that monitors the voltage output from the power supply unit I. a battery 4 that supplies information retention voltage to the memory (RAM) 2 when the voltage output from the power supply unit 1 becomes below a specified voltage; When an abnormality in the voltage is detected, the detection signal ■ connects the power supply unit 1 and the memory (RA
M) A changeover switch section 5 that disconnects the connection with 2.
and a wI control unit 6 that controls various internal processing operations.

As shown in FIG. 4, when the output from the power supply section 1 rises to the voltage Von, the power supply monitoring section 3 turns on the detection signal ■ to put the changeover switch section 5 in a short-circuit state.

On the other hand, when the output drops to the voltage Voff, the detection signal ■
is turned off, the selector switch unit 5 is opened, and the connection with the memory (RAM) 2 is disconnected.

Normally, the voltage supplied to the memory (RAM) 2 is operated by receiving the output voltage from the power supply section (2). However, when the power supply monitoring section 3 detects that the output voltage from the power supply section 1 has dropped to the voltage Voff, the detection signal ■ turns off, and the changeover switch section 5 switches between the power supply section 1 and the memory (RAM).
Disconnect from 2.

When this state occurs, the subsequent memory (RAM) 2
Voltage is supplied to the battery 4 via a resistor E. On the other hand, the power supply monitoring section 3 notifies the control section 6 of a power supply abnormality or a power-off state, and also displays the state by a signal (2) using a circuit not shown to alert the operator.

Further, when the control unit 6 confirms that there is a power abnormality or a power outage state,
From then on, the memory (RAM)
Control is performed to stop writing information to 2. It is assumed that the battery 4 is rechargeable and is always in a charged state at that voltage when the power supply unit 1 is supplying voltage to the memory (RAM) 2.

[Problem that the invention seeks to solve]

In the conventional system, the battery 4 installed for the above-mentioned purpose is normally connected in a charging state, so it is used assuming that it has a sufficient current capacity.

However, for example, if the output of the power supply unit 1 is cut off and the battery 4 is used as a backup for a long time, or if there is some kind of failure (e.g. due to end of life, etc.), the voltage is sufficient to maintain the data stored in the memory (RAM) 2 normally. Even if it cannot be supplied, the abnormal state will not be confirmed until the stored data is read and processed.

That is, small electronic devices such as this terminal device generally do not have a function to check the output voltage and function of the battery 4.

Therefore, if the battery 4 cannot fully perform its functions due to its lifespan or other reasons, even if the battery 4 is in a charging state with the voltage supplied from the power supply unit 1, the battery is not charged with sufficient charging voltage due to functional deterioration etc. If a holding voltage is supplied to the memory (RAM) 2 in step 4, the stored data will become unreliable.

Furthermore, even when a check function is provided, a backup method including a back amplifier power source is often adopted, which causes problems such as making the device expensive.

[Means for solving problems]

FIG. 1 shows a block diagram illustrating the invention in detail.

The principle block diagram shown in FIG. 1 mainly shows the outline of the block configuration for checking the output voltage of the battery 4 that backs up the voltage supply to the memory (RAM) 2, and the block diagram is similar to that explained in FIG. 3. Power supply part 1
．． Memory (RAM) 2゜Power supply monitoring section 3. Battery 4, battery abnormality detection means (battery abnormality detection unit) 10 that checks the output voltage status of battery 4 with a load connected, and a battery check completion signal output from the battery abnormality detection means (battery abnormality detection) 10. When ■ is confirmed, a control means (control unit) 20 sends out a charge start signal ■ instructing to start charging the battery 4, and when the charge start signal ■ from the control means (control unit) 20 is turned on, a power supply unit 1 and a battery 4, and a battery charge control means (battery charge control section) 30 that connects the battery 4 to the battery 4 and brings the battery 4 into a charging state.

[Effect]

Supplying operating voltage from the power supply unit to the memory (RAM),
When starting charging the bank-up pantry, check the battery output voltage status with the battery normal detection means (with the load connected) before starting charging the battery.
(battery abnormality detection unit), and sends the check result as a battery check completion signal to the control means (control unit) and notifies it.

On the other hand, the controller that confirmed this buffer check end signal
The 41g means (control unit) turns on a charge start signal that instructs to start charging the battery, causes the battery to start charging from the power supply unit via the battery charge control means (battery charge control unit), and also controls the charging of the battery. By configuring the device to display status information, it is possible to check the output voltage of the battery with a simple circuit configuration, and it is also possible to quickly and reliably grasp the reliability of the data stored in the memory.

〔Example〕

The gist of the present invention will be specifically explained below with reference to an embodiment shown in FIG.

FIG. 2 shows a block diagram illustrating the invention in detail. Note that the same reference numerals refer to the same objects throughout the plan.

The battery abnormality detection unit 10 of this embodiment includes a NOT circuit 11 that sends a NOT signal of the charging start signal (■) from the control unit 20, and a NOT circuit (NO) of the detection signal (■) and the charging instruction signal (■) from the power source monitoring unit 3.
NO circuit 12 and the detection signal ■ to take the AND with the T signal
is on and the charging start signal ■ is off, a short circuit will occur,
A switch section 13 that is open when the detection signal ■ is off or a charging start signal ■ is on, and an output voltage of the battery 4 that is applied to the load resistor F when the switch section 13 is short-circuited are created by a circuit not shown. The comparison unit 14 compares the voltage with a reference voltage (corresponding to the voltage Voff) (corresponding to the voltage Voff) and sends out the comparison result as a battery check completion signal (2).

Furthermore, when the control unit 20 of this embodiment confirms the battery check completion signal ■ from the comparison unit 14, it includes a signal recognition unit that sends a confirmation signal ■ to the charging instruction signal generation unit 22 and a display unit (not shown). 21, and the confirmation signal ■ from the signal recognition unit 21 generates a charging start signal ■
and a charging instruction signal generating section 22 that sends out an order.

Furthermore, the battery charging control unit 30 of this embodiment has a NUT that sends out a NOT signal of the detection signal ① from the power supply monitoring unit 3.
An OR circuit 3 that calculates the logical sum of the charge start signal (■) from the control unit 20 and the NOT signal of the detection signal (■) from the NOT circuit 31.
2, and a switch section 33 that shorts when the detection signal (2) is off or the charging start signal (2) is on, and becomes an oven when the detection signal (2) is on and the charging start signal (2) is off.

Next, the operation of checking the output voltage of the battery 4 in this embodiment will be explained.

(1) When the power supply unit 1 is turned on, the output voltage of the power supply unit 1 rises and reaches the voltage Von (Von shown in FIG. 4), the power supply monitoring unit 3 turns on the detection signal ■, and the changeover switch unit 5 Short-circuit the memory (RAM) 2
supply voltage to Incidentally, at this point, the charging start signal (2) is in an off state.

(2) In this state, the switch section 33 sends the voltage detection signal ■
is on and the charging instruction signal (■) is off, the oven state is reached, the switch part 13 is shorted, and the battery 4 is in the oven state.
The output voltage of is applied to the load resistor F.

Thereby, the comparator 14 checks the state of the output voltage of the battery 4 by comparing it with the reference voltage (2) output from a circuit (not shown).

(3) If the output voltage of the battery 4 is below the specified voltage at this time, the comparator 14 determines that the battery abnormality is the battery check completion ■, and the signal recognition unit 2 in the control unit 2o
Send to 1.

The signal recognition unit 21 thereby confirms the abnormality display signal.■
The signal is sent to the charging instruction signal generating section 22 and an alarm display circuit (not shown) to indicate a battery abnormality (insufficient battery voltage).

At the same time, the charging instruction signal generating section 22 turns on the charging start signal (2) and sends it to the switch section 13.33. As a result, the switch section 13 is in an open state, the switch section 33 is in a short-circuit state, and the battery 4 is in a charging state with the output voltage of the power supply section 1. After that, the output voltage of the power supply section 1 is cut off.
This state continues until the time of restart.

(4) If a battery abnormality (insufficient battery voltage) is displayed, the data stored in the memory (RAM) 2 is recognized as unreliable.

Further, if the output voltage of the battery 4 is within the specified voltage, a display to that effect is displayed.

In this way, by checking the state of the output voltage of the battery using a simple method when the power supply section 1 is turned on, the state of the output voltage at the time of bank up for the memory (1?AM) 2 can be easily grasped.

〔Effect of the invention〕

According to the present invention as described above, since the output voltage of the battery can be easily checked with a simple circuit configuration, there is an effect that an abnormality can be detected early and reliably.

[Brief explanation of drawings]

Fig. 1 is a block diagram explaining the present invention in detail, Fig. 2 is a block diagram explaining the present invention in detail, Fig. 3 is a block diagram explaining the conventional example, and Fig. 4 explains the power supply voltage monitoring situation. The figures shown below are respectively shown. In the figure, 1 is a power supply unit, 2 is a memory (RAM), and 3 is a power supply unit.
is a power supply monitoring section, 4 is a battery, 5 is a selector switch section, 6.20 is a control section, 10 is a battery abnormality detection section, 11.31 is a NOT circuit, 12 is an AND circuit, 1
3.33 is a switch section, 14 is a comparison section, 21 is a signal recognition section, 22 is a charging instruction signal generation section, and 32 is an OR circuit. A picture explaining 1 foot of rice and 1 chile... 72, edge 3I21
' PL status of each power source voltage 5C day off month Hatake 4th close

Claims (1)

[Claims] A device that can be charged externally and is equipped with a battery (4) that backs up the holding voltage for the memory (2) when the voltage supply from the power supply section (1) is cut off. and a battery abnormality detection means (10) for checking the output voltage of the battery (4) with a load connected and notifying the control means (20) of the check status by a battery check completion signal ([3]); , when the battery check end signal ([3]) is input, a control means for instructing the battery charging control means (30) to start charging the battery (4) with a charge start signal ([4]); (20), and a battery charging control means (30) that starts charging the battery (4) from the power supply section (1) when the charge start signal ([4]) from the control means (20) is on. ), and when the power supply unit (1) starts operating, the battery (4) is installed.
), the output voltage of the battery (4) is checked by the battery abnormality detection means (10) by connecting it to the load within the battery abnormality detection means (10), and the check status is checked. The battery charge control means (30) is turned on by the charge start signal ([4]) from the control means (20) notified by the battery check end signal ([3]), and the battery charge control means (30) is turned on.
A battery backup method characterized by keeping the battery in a charging state.