JPS563500A - Battery backup circuit for memory - Google Patents

Battery backup circuit for memory

Info

Publication number
JPS563500A
JPS563500A JP7987579A JP7987579A JPS563500A JP S563500 A JPS563500 A JP S563500A JP 7987579 A JP7987579 A JP 7987579A JP 7987579 A JP7987579 A JP 7987579A JP S563500 A JPS563500 A JP S563500A
Authority
JP
Japan
Prior art keywords
voltage
memory
power source
source
main power
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP7987579A
Other languages
Japanese (ja)
Other versions
JPS5938676B2 (en
Inventor
Tsuguyoshi Hayashi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Electric Corp
Original Assignee
Mitsubishi Electric Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mitsubishi Electric Corp filed Critical Mitsubishi Electric Corp
Priority to JP54079875A priority Critical patent/JPS5938676B2/en
Publication of JPS563500A publication Critical patent/JPS563500A/en
Publication of JPS5938676B2 publication Critical patent/JPS5938676B2/en
Expired legal-status Critical Current

Links

Landscapes

  • Stand-By Power Supply Arrangements (AREA)
  • Power Sources (AREA)
  • Static Random-Access Memory (AREA)
  • Techniques For Improving Reliability Of Storages (AREA)

Abstract

PURPOSE: To ensure the effective memory holding even to the sudden change of the main power source, by giving the backup switching in correspondence to the voltage change of the main power source via the serial circuit of two sets of Zener diodes and the resistance.
CONSTITUTION: No current flows to Zener diodes 13 and 17 connected in series to resistances 12 and 18 each when the voltage of main power source 6 has the zero potential. Thus transistors 15, 20 and 21 are turned off, and the voltage of backup power source 7 is applied to voltage terminal 2a of CMOS memory 2 to hold the memory of memory 2. When the voltage of source 6 increases higher than source 7, the current flows to diode 17 to produce the switching signal. As a result, transistors 20 and 21 conduct, and the voltage of source 6 is applied to memory 2. When the voltage of source 6 increases more, diode 13 conducts to increase the voltage of terminal 2d. Thus memory 2 becomes workable via CPU1 to carry out the contactless action in response to the voltage of the main power source immediately. As a result, a backup circuit which is capable of the effective memory holding even to the sudden change of the power source.
COPYRIGHT: (C)1981,JPO&Japio
JP54079875A 1979-06-22 1979-06-22 Memory battery backup circuit Expired JPS5938676B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP54079875A JPS5938676B2 (en) 1979-06-22 1979-06-22 Memory battery backup circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP54079875A JPS5938676B2 (en) 1979-06-22 1979-06-22 Memory battery backup circuit

Publications (2)

Publication Number Publication Date
JPS563500A true JPS563500A (en) 1981-01-14
JPS5938676B2 JPS5938676B2 (en) 1984-09-18

Family

ID=13702393

Family Applications (1)

Application Number Title Priority Date Filing Date
JP54079875A Expired JPS5938676B2 (en) 1979-06-22 1979-06-22 Memory battery backup circuit

Country Status (1)

Country Link
JP (1) JPS5938676B2 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59126298A (en) * 1983-01-06 1984-07-20 株式会社日立製作所 Radioactive waste final disposal container
JPS59130297U (en) * 1983-02-19 1984-09-01 株式会社日本テクナ−ト memory backup circuit
US12395146B2 (en) 2020-09-10 2025-08-19 Ngk Insulators, Ltd. Composite substrate for acoustic wave device

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59126298A (en) * 1983-01-06 1984-07-20 株式会社日立製作所 Radioactive waste final disposal container
JPS59130297U (en) * 1983-02-19 1984-09-01 株式会社日本テクナ−ト memory backup circuit
US12395146B2 (en) 2020-09-10 2025-08-19 Ngk Insulators, Ltd. Composite substrate for acoustic wave device

Also Published As

Publication number Publication date
JPS5938676B2 (en) 1984-09-18

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