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US4646264A Expired / Lapsed US ⏱️ 0.0 years remaining

Programmable read-only memory device

Assignee: Fujitsu Ltd
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Filing: 1983-06-20
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Granted: 1987-02-24
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Expires: 2003-06-20
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Abstract

Abstract A programmable ROM device comprising, for example, junction-shorting-type or fuse-blown-type memory cells, connected between word lines and bit lines, in which device information is written into a selected memory cell by applying a high voltage to a terminal such as a CE terminal and by applying a write-in current to the bit line connected to the selected memory cell and in which leakage of the write-in current into memory cells adjacent to the selected memory cell is prevented, thereby providing a reliable information-storing operation.

Inventors

  • 👤 Yasurou Matsuzaki

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 21:07
CPC Classifications
G; G11; G11C; G11C17/00; G11C17/14; G11C17/18

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 171 words
A programmable read-only memory device operatively connected to receive a word line selecting address signal, comprising: word lines; bit lines intersecting said word lines; memory cells operatively connected at the intersections of said word lines and said bit lines, the writing of information into one of said memory cells being effected by selecting corresponding ones of said word lines and bit lines connected to said one of said memory cells into which information is to be written by rendering the potential of said corresponding one of said word lines low, and by applying a write-in current to said corresponding one of said bit lines; and a pull-up circuit, operatively connected to said word lines and operatively connected to receive the word line selecting address signal, for pulling up the potential of nonselected word lines, and applying a high voltage to every other one of said non-selected word lines, said high voltage being equal to or higher than the voltage applied to a selected bit line when a write-in operation is effected.
Claim 2
Dependent Claim 171 words
A programmable read-only memory device operatively connected to receive a word line selecting address signal, comprising: word lines; bit lines intersecting said word lines; memory cells operatively connected at the intersections of said word lines and said bit lines, the writing of information into one of said memory cells being effected by selecting corresponding ones of said word lines and bit lines connected to said one of said memory cells into which information is to be written by rendering the potential of said corresponding one of said word lines low, and by applying a write-in current to said corresponding one of said bit lines; and a pull-up circuit, operatively connected to said word lines and operatively connected to receive the word line selecting address signal, for pulling up the potential of nonselected word lines, and applying a high voltage to every other one of said non-selected word lines, said high voltage being equal to or higher than the voltage applied to a selected bit line when a write-in operation is effected.
Claim 3
Dependent Claim 33 words
A programmable read-only memory device according to claim 1, wherein said pull-up circuit for non-selected word lines is activated only by a signal generated by one bit of the word line-selecting address signal.
Claim 4
Dependent Claim 33 words
A programmable read-only memory device according to claim 2, wherein the signal generated by one bit of the word line selecting address is the least significant bit of said word line-selecting address signal.
Claim 5
Dependent Claim 32 words
A programmable read-only memory device according to claim 1, wherein the high voltage supplied by said pull-up circuit for said non-selected word lines is applied to all of said non-selected word lines.
Claim 6
Dependent Claim 54 words
A programmable read-only memory device according to claim 1, wherein said pull-up circuit for said non-selected word lines comprises: address inverters, operatively connected to receive the word line selecting address signal, for providing output signals; and a switching circuit, operatively connected to said address inverters, controlled by the output signals from said address inverters.
Claim 7
Dependent Claim 41 words
A programmable read-only memory device according to claim 5, further comprising word line address inverters operatively connected to said word lines, wherein said address inverters receive the word line address signal through said word line address inverters for word line selection.
Claim 8
Dependent Claim 20 words
A programmable read-only memory device according to claim 1, wherein each of said memory cells is a junction-shorting-type memory cell.
Claim 9
Dependent Claim 20 words
A programmable read-only memory device according to claim 1, wherein each of said memory cells is a fuse-blown-type memory cell.
Claim 10
Dependent Claim 110 words
A programmable read-only memory device, operatively connected to receive a word line selecting address signal including word lines, bit lines intersecting the word lines, and memory cells operatively connected at the intersections of word lines and bit lines, comprising: a pull-up circuit, operatively connected to the word lines, for pulling up the potential of non-selected word lines to a high voltage level higher than the voltage level of selected word lines, comprising: a first pull-up unit for pulling up the potentials of odd numbered non-selected word lines; and a second pull-up unit, operatively connected to said first pull-up unit, for pulling up the potentials of even numbered non-selected word lines.
Claim 11
Dependent Claim 110 words
A programmable read-only memory device, operatively connected to receive a word line selecting address signal including word lines, bit lines intersecting the word lines, and memory cells operatively connected at the intersections of word lines and bit lines, comprising: a pull-up circuit, operatively connected to the word lines, for pulling up the potential of non-selected word lines to a high voltage level higher than the voltage level of selected word lines, comprising: a first pull-up unit for pulling up the potentials of odd numbered non-selected word lines; and a second pull-up unit, operatively connected to said first pull-up unit, for pulling up the potentials of even numbered non-selected word lines.
Claim 12
Dependent Claim 218 words
A programmable read-only memory device operatively connected to receive a word line selecting address signal, comprising: word lines; bit lines intersecting said word lines; memory cells operatively connected at the intersections of said word lines and said bit lines, the writing of information into one of said memory cells being effected by selecting corresponding ones of said word lines and bit lines connected to said one of said memory cells into which information is to be written by rendering the potential of said corresponding one of said word lines low, and by applying a write-in current to said corresponding one of said bit lines; and a pull-up circuit, operatively connected to said word lines and operatively connected to receive the word line selecting address signal, for pulling up the potential of non-selected word lines and applying a high voltage to said non-selected word lines, said high voltage being equal to or higher than the voltage applied to a selected bit line when a write-in operation is effected, said pull-up circuit for non-selected word lines being activated only by a signal generated by one bit of the word line selecting address signal and said word lines are disposed so that the high voltage supplied by said pull-up circuit for non-selected word lines is applied to every other word line.
Claim 13
Dependent Claim 218 words
A programmable read-only memory device operatively connected to receive a word line selecting address signal, comprising: word lines; bit lines intersecting said word lines; memory cells operatively connected at the intersections of said word lines and said bit lines, the writing of information into one of said memory cells being effected by selecting corresponding ones of said word lines and bit lines connected to said one of said memory cells into which information is to be written by rendering the potential of said corresponding one of said word lines low, and by applying a write-in current to said corresponding one of said bit lines; and a pull-up circuit, operatively connected to said word lines and operatively connected to receive the word line selecting address signal, for pulling up the potential of non-selected word lines and applying a high voltage to said non-selected word lines, said high voltage being equal to or higher than the voltage applied to a selected bit line when a write-in operation is effected, said pull-up circuit for non-selected word lines being activated only by a signal generated by one bit of the word line selecting address signal and said word lines are disposed so that the high voltage supplied by said pull-up circuit for non-selected word lines is applied to every other word line.
Claim 14
Dependent Claim 34 words
A programmable read-only memory device according to claim 10, wherein the signal generated by one bit of the word line selecting address is the least significant bit of said word line selecting address signal.

References Cited (Backward Citations)

US4287569A Cited
US4369503A Cited
US4488261A Cited
US4511811A Cited
US4554469A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-02-23 1990-08-25 1991-02-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-02-23 1994-08-25 1995-02-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-02-23 1998-08-25 1999-02-24 $7700.00 Window Closed / Lapsed

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