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US4734889A Expired / Lapsed US ⏱️ 0.0 years remaining

Semiconductor memory

Assignee: Mitsubishi Electric Corp
•
Filing: 1986-03-06
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Granted: 1988-03-29
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Expires: 2006-03-06
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Abstract

Abstract A spare Y decoder is provided with MOS transistors 14 and 20 for charge on both sides of a parasitic resistor 19. As a result, nodes N1 and N2 are rapidly charged by the MOS transistors 20 and 14 for charge, respectively.

Inventors

  • 👤 Koichiro Mashiko
  • 👤 Yoshikazu Morooka
  • 👤 Tadato Yamagata
  • 👤 Yuto Ikeda

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 14:44
CPC Classifications
G; G11; G11C; G11C29/00; G11C29/70; G11C29/78; G11C29/84

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 39 words
A semiconductor memory of a redundant design having a spare decoder and a regular decoder, characterized in that: a plurality of charging means are provided in said spare decoder, each said charging means comprising a switched constant voltage source.
Claim 2
Dependent Claim 39 words
A semiconductor memory of a redundant design having a spare decoder and a regular decoder, characterized in that: a plurality of charging means are provided in said spare decoder, each said charging means comprising a switched constant voltage source.
Claim 3
Dependent Claim 76 words
A semiconductor memory in accordance with claim 1, comprising: a memory cell array in which memory cells are regularly arrayed and an arbitrary memory cell can be specified by a column address and a row address, said spare decoder being located outside said memory cell array, said semiconductor memory having a parasitic resistor connected between said spare decoder and said memory cell array, and said charging means being provided on both sides of said parasitic resistor.
Claim 4
Dependent Claim 27 words
A semiconductor memory in accordance with claim 2, wherein said spare decoder is a spare column decoder for decoding said column address of said memory cell array.
Claim 5
Dependent Claim 27 words
A semiconductor memory in accordance with claim 2, wherein said spare decoder is a spare row decoder for decoding said row address of said memory cell array.
Claim 6
Dependent Claim 189 words
A semiconductor memory of a redundant design comprising: a memory cell array in which a plurality of memory cells are regularly arrayed along a plurality of word lines and a plurality of bit lines perpendicular to said word lines and an arbitrary one of said memory cells can be specified by the combination of a column address and a row address, reading means for selecting one of said word lines by said row address to read out onto said bit lines, an information charge of the memory cells connected to said selected one of said word lines, means for selecting one of said bit lines by said column address to provide to a device located external to said semiconductor memory the information charge amplified by said sense amplifier connected to said selected one of said bit lines, and a spare column decoder for selecting a spare bit line when a column address corresponding to a defective bit line is applied, said semiconductor memory being characterized in that a plurality of charging means are provided in said spare column decoder, each said charging means comprising a switched constant voltage source.
Claim 7
Dependent Claim 189 words
A semiconductor memory of a redundant design comprising: a memory cell array in which a plurality of memory cells are regularly arrayed along a plurality of word lines and a plurality of bit lines perpendicular to said word lines and an arbitrary one of said memory cells can be specified by the combination of a column address and a row address, reading means for selecting one of said word lines by said row address to read out onto said bit lines, an information charge of the memory cells connected to said selected one of said word lines, means for selecting one of said bit lines by said column address to provide to a device located external to said semiconductor memory the information charge amplified by said sense amplifier connected to said selected one of said bit lines, and a spare column decoder for selecting a spare bit line when a column address corresponding to a defective bit line is applied, said semiconductor memory being characterized in that a plurality of charging means are provided in said spare column decoder, each said charging means comprising a switched constant voltage source.
Claim 8
Dependent Claim 35 words
A semiconductor memory in accordance with claim 5, having a parasitic resistor connected between said column decoder and said memory cell array, and said charging means are provided on both sides of said parasitic resistor.

References Cited (Backward Citations)

US4586170A Cited
US4601017A Cited
US4592027A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-03-29 1991-09-28 1992-03-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-03-29 1995-09-28 1996-03-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-03-29 1999-09-28 2000-03-29 $7700.00 Window Closed / Lapsed

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