JPH05134940A - Static memory device and its memory back-up system - Google Patents

Abstract

PURPOSE:To lose neither a file nor a data even though a main power supply is cut off. CONSTITUTION:When a main power supply 1 is cut off, a power supply control circuit 3 switches the supply 1 to an auxiliary power supply 2. Therefore the register contents of a CPU 4 are immediately written into a static memory device 6 which contains a back-up battery. Then the resettable information is backed up when the power is supplied again from the supply 1. When the power is supplied from the supply 1 while the memory is kept in the device 6 and a static memory 5 containing a battery, these memory devices are not checked.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a static type memory device used in information processing equipment such as a computer and a word processor, and a memory backup system thereof.

[0002]

2. Description of the Related Art In a conventional static memory device, the contents held until then are lost immediately when the power supply is stopped.

[0003]

In the conventional static memory device described above, the power supply is immediately cut off when the power switch is erroneously pressed during the operation of the information processing device or a power failure occurs. Since the save operation of the files and data inside cannot be performed, there is a problem that necessary files and data are lost.

[0004]

The static type memory device of the first invention is characterized by having a built-in rechargeable backup battery.

The memory backup system of the second invention is
A static memory device having a rechargeable backup battery therein, and a power supply control circuit for switching the power supply from the main power supply to the auxiliary power supply when the power is turned off and for storing the contents of the central processing unit in the static memory device are provided. The memory is not checked when the memory is held in the static memory device when the power is turned on.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a static type memory device of the first invention, and FIG. 2 is a block diagram showing an embodiment of a memory backup system of the second invention.

In FIG. 1, a static type memory device 6 with a built-in backup battery is a static memory I.
Static memory IC6 for C61, charging source and ground source
The rechargeable backup battery 62 shared with the No. 1 is contained in one chip.

In FIG. 2, when the main power supply signal 01 is supplied from the main power supply unit 1, the power supply control circuit 3 includes a central processing unit 4, a static type memory with built-in battery 5, a static type memory device with built-in backup battery. Power supply signals 03, 04, 05 are supplied to each of the terminals 6. Further, data is exchanged between the central processing unit 4 and the static type memory 5 with a built-in battery only by the access signals 06 and data signals 07.

When the supply of the main power supply signal 01 from the main power supply 1 is cut off, the power supply control circuit 3 immediately receives the auxiliary power supply signal 02 from the auxiliary power supply 2 and the central processing unit 4, the static memory with a built-in battery 5, and the backup. Power supply signals 03, 04, 05 to the static memory device 6 with built-in battery
Continue to supply. Then, the central processing unit 4 cancels the access signal 06 to the static type memory 5 with built-in battery, transmits the data signal 08 to the static type memory device 6 with built-in battery for backup, and registers the registers necessary when the main power supply 1 is restored. Write the content. As a result, since the static memory 5 with built-in battery and the static memory device 6 with built-in backup battery have a built-in battery in one chip of the memory, while the battery is being charged, the main power supply 1, the auxiliary power supply 2 Therefore, even if the main power supply signal 01 and the auxiliary power supply signal 02 are stopped and the supply of the power supply signals 03, 04, 05 from the power supply control circuit 3 is cut off, the information that can be restored is saved.

When the power source signal 01 is supplied again from the main power source 1, the central processing unit 4 does not perform the memory check of the static type memory 5 with built-in battery and the static type memory device 6 with built-in battery for backup, and the static type built-in battery for backup is used. The contents of the memory device 6 are written in the register section by the data signal 09.

[0011]

As described above, according to the present invention, even when the user mistakenly presses the power switch or a power failure occurs, the battery connected to the static type memory is supplied again while the power is being supplied. When the main power is turned on, files and data are not lost, and the work can be continued in the state when the power is turned off.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a static memory device of the first invention.

FIG. 2 is a block diagram showing an embodiment of a memory backup system of the second invention.

[Explanation of symbols]

1 Main Power Supply 2 Auxiliary Power Supply 3 Power Control Circuit 4 Central Processing Unit 5 Static Memory with Built-in Battery 6 Static Memory Device with Built-in Battery for Backup 01 Main Power Signal 02 Auxiliary Power Signal 03, 04, 05 Power Signal 06 Access Signal 07, 08 , 09 Data signal 61 Static memory IC 62 Battery for backup

Claims (2)

[Claims] 1. A static memory device having a built-in rechargeable backup battery. 2. A static memory device having a rechargeable backup battery therein, and a power supply for switching the power supply from a main power supply to an auxiliary power supply when the power is turned off and for storing the contents of the central processing unit in the static memory device. A memory backup system comprising a control circuit, wherein the memory is not checked when the power is turned on when the memory is held in the static memory device.