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US5075887A Expired / Lapsed US ⏱️ 0.0 years remaining

Semiconductor memory capable of improving data rewrite speed

Assignee: Toshiba Corp
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Filing: 1991-01-28
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Granted: 1991-12-24
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Expires: 2011-01-28
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Abstract

Abstract A semiconductor memory device is disclosed which comprises, as shown in FIG. 1, a pair of column lines, memory cells connected to the corresponding column lines, a sense amplifier connected to the column lines, row lines for selecting the memory cells in accordance with a row address signal, and first and second transistors having their current paths connected between the column lines and a fixed potential supply terminal supplied with a positive power source potential or a ground potential, wherein the gates of the first and second transistors are connected to the first and second row lines for a data rewrite operation which can be selected independently of the row line.

Inventors

  • 👤 Koichi Magome
  • 👤 Masakazu Kiryu
  • 👤 Shigeo Ohshima
  • 👤 Haruki Toda
  • 👤 Hiroshi Sahara

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 10:18
CPC Classifications
G; G11; G11C; G11C11/00; G11C11/21; G11C11/34; G11C11/40; G11C7/00; G11C7/20; G11C11/401; G11C11/4063; G11C11/407; G11C11/4072; G11C11/409

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 159 words
A semiconductor memory device comprising: first and second column lines (BL, BL); a plurality of memory cells (C1, Q1, C2, Q2) connected to said column lines; a sense amplifier (SA) connected to said column lines; row lines (WL0, WL1) for selecting the memory cells in accordance with a row address signal; and first and second transistors (Q3, Q4) connected at their current paths between said pair of column lines and a fixed potential supply terminal supplied with a positive power source potential or ground potential; wherein said first and second transistors are connected at their gates to first and second data rewrite row lines which can be selected independently of said row lines, such that said first and second transistors are operated independently by first and second timing control signals which are respectively input to said first and second transistors, and wherein said plurality of memory cells are formed between said sense amplifier and said first and second transistors.
Claim 2
Dependent Claim 159 words
A semiconductor memory device comprising: first and second column lines (BL, BL); a plurality of memory cells (C1, Q1, C2, Q2) connected to said column lines; a sense amplifier (SA) connected to said column lines; row lines (WL0, WL1) for selecting the memory cells in accordance with a row address signal; and first and second transistors (Q3, Q4) connected at their current paths between said pair of column lines and a fixed potential supply terminal supplied with a positive power source potential or ground potential; wherein said first and second transistors are connected at their gates to first and second data rewrite row lines which can be selected independently of said row lines, such that said first and second transistors are operated independently by first and second timing control signals which are respectively input to said first and second transistors, and wherein said plurality of memory cells are formed between said sense amplifier and said first and second transistors.
Claim 3
Dependent Claim 19 words
The semiconductor memory device according to claim 1, wherein said memory cells each comprises one transistor and one capacitor.
Claim 4
Dependent Claim 151 words
A semiconductor memory device according to claim 1, further comprising third and fourth transistors (Q7, Q8); wherein said third transistor (Q7) is connected to said first column line (BL), and interposed between said sense amplifier (SA) and said first transistor (Q3); said fourth transistor (Q8) is connected to said second column line (BL), and interposed between said sense amplifier (SA) and said second transistor (Q4); the length of said first column line between said third transistor (Q7) and said means amplifier (SA) is equal to that of said second column line between said fourth transistor (Q8) and said sense amplifier (SA); said third and fourth transistors are further connected to data supply terminals (IN, IN); and said third and fourth transistors are in an on-state while data signals are being input from said data supply terminals (IN, IN), and are in an off-state while no signals are input from the same.
Claim 5
Dependent Claim 19 words
The semiconductor memory device according to claim 3, wherein said memory cells each comprises one transistor and one capacitor.
Claim 6
Dependent Claim 23 words
The semiconductor memory device according to claim 3, wherein said data supply terminals are grounded or connected to a positive power source terminal.
Claim 7
Dependent Claim 44 words
The semiconductor memory device according to claim 3, wherein one of said data supply terminals is connected to said switching transistors via an inverter which is supplied with input write data and the other data supply terminal is placed in an electrically floated state.
Claim 8
Dependent Claim 19 words
The semiconductor memory device according to claim 3, wherein a common signal line is connected to the switching transistors.
Claim 9
Dependent Claim 66 words
The semiconductor memory device according to claim 7, wherein when said common signal line becomes a predetermined level subsequent to the selection of said column and row lines and a potential on said column line becomes a predetermined level, said sense amplifier sets said potential on said column line to a predetermined level to allow predetermined data "0" or "1" to be written into said cells.
Claim 10
Dependent Claim 39 words
The semiconductor memory device according to claim 3, further comprising a buffer which, upon receipt of an input signal of a predetermined level, writes predetermined data "0" or "1" into all cells on said row line at one time.
Claim 11
Dependent Claim 180 words
A semiconductor device having a fixed potential supply terminal for connection to a positive power source potential or a ground potential, and receiving first and second timing control signals and a row address signal, the semiconductor device comprising: first and second column lines (BL, BL); a plurality of memory cells (C1, Q1, C2, Q2) connected to the column lines; a sense amplifier (SA) connected to the column lines; normal row lines (WL0, WL1) for selecting the memory cells in accordance with the row address signal; first and second transistors, each having a current path, and being connected at their current paths between the first and second column lines and the fixed potential supply terminal, each receiving a respective one of the first and second timing control signals; and first and second data rewrite row lines respectively connected to the gates of the first and second transistors and responsive to the first and second timing control signals for selection independently of the normal row lines; the plurality of memory cells being between the sense amplifier and the first and second transistors.
Claim 12
Dependent Claim 180 words
A semiconductor device having a fixed potential supply terminal for connection to a positive power source potential or a ground potential, and receiving first and second timing control signals and a row address signal, the semiconductor device comprising: first and second column lines (BL, BL); a plurality of memory cells (C1, Q1, C2, Q2) connected to the column lines; a sense amplifier (SA) connected to the column lines; normal row lines (WL0, WL1) for selecting the memory cells in accordance with the row address signal; first and second transistors, each having a current path, and being connected at their current paths between the first and second column lines and the fixed potential supply terminal, each receiving a respective one of the first and second timing control signals; and first and second data rewrite row lines respectively connected to the gates of the first and second transistors and responsive to the first and second timing control signals for selection independently of the normal row lines; the plurality of memory cells being between the sense amplifier and the first and second transistors.

References Cited (Backward Citations)

US4439843A Cited
US4567578A Cited
US4581720A Cited
US4847809A Cited
JPS62121997A Cited
US4837746A Cited
JPS62184693A Cited
US4739500A Cited
US4789967A Cited
US4829484A Cited
US4907199A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-12-23 1995-06-24 1995-12-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-12-23 1999-06-24 1999-12-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-12-23 2003-06-24 2003-12-24 $7700.00 Window Closed / Lapsed

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