EP0515103A2
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Integrated semiconductor content addressable memory circuit
Assignee: JFE Steel Corp
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Filing: 1992-05-15
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Granted: —
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Expires: 2012-05-15
Abstract
Abstract A semiconductor integrated circuit is a CAM memory which comprises at least one memory cell including a first storage unit for defining the electrical connection and otherwise the non-connection between a first data line and a match line and a second storage unit for defining the electrical non-connection and otherwise the connection between a second data line and the match line, and a control word line for controlling said first and second storage units in the memory cell, the match line corresponding to at least one of the control word lines, the control word line being used to effect the connection and otherwise non-connection between each of said first and second data lines and the match line in accordance with the definition of connections of said first and second storage units. Moreover, the storage unit can be composed of a coupler or a nonvolatile memory element such as a MONOS-type nonvolatile memory element, PROM, EPROM, EEPROM, UVEPROM and a like, and the memory cell further may include at least one selective transistor. The CAM memory comprises at least one of potential detecting means for detecting an electric potential of the match line, holding means for holding the result of detection in response to each control word line and preventing means for preventing the through current between the memory cells in conformity with and in nonconformity with the retrieval data. Therefore, the semiconductor integrated circuit can construct a large scale integrated CAM which permits data to be read out and written flexibly and data to be retrieved from a large number of memory cells without electrical and mutual interference, simultaneously with the building-up of a high-speed, large capacity data base.
Inventors
- 👤 Masato c/o Kawasaki Steel Corporation YONEDA
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 08:53
CPC Classifications
G; G11; G11C; G11C15/00; G11C15/04; G11C15/046
Claims Analysis
Total Claims: 70
Claim 1
Independent Claim
144 words
A semiconductor integrated circuit comprising a memory cell including a first storage unit for defining the electrical connection and otherwise the non-connection between a first data line and a match line and a second storage unit for defining the electrical non-connection and otherwise the connection between a second data line and said match line, at least a selective transistor provided between at least one of said first and second storage units of the memory cell and said match line or between said first and second storage units and said first and second data lines, and a control word line for controlling said selective transistor, said control word line being used to effect the connection and otherwise non-connection between each of said first and second data lines and said match line in accordance with the definition of connections of said first and second storage units.
Claim 2
Dependent Claim
22 words
A semiconductor integrated circuit according to claim 1, wherein said storage unit for defining the electrical connection is composed of a coupler.
Claim 3
Dependent Claim
19 words
A semiconductor integrated circuit according to claim 1, wherein said storage unit is composed of a nonvolatile memory element.
Claim 4
Dependent Claim
34 words
A semiconductor integrated circuit according to claim 1, wherein both said first and second storage units are composed of a nonvolatile memory element and each nonvolatile memory element is connected to each selective transistor.
Claim 5
Dependent Claim
21 words
A semiconductor integrated circuit according to claim 3 or 4, wherein said nonvolatile memory element is a MONOS-type nonvolatile memory element.
Claim 6
Dependent Claim
30 words
A semiconductor integrated circuit according to anyone of claims 1 to 5, wherein said match line further has potential detecting means for detecting an electric potential of said match line.
Claim 7
Dependent Claim
29 words
A semiconductor integrated circuit according to anyone of claims 1 to 6, wherein said match line further has fixing means for fixing an electric potential of said match line.
Claim 8
Dependent Claim
67 words
A semiconductor integrated circuit according to anyone of claims 1 to 7, wherein said control word line further has potential non-fixing means and connection means for connecting to said match line, said connection means and said potential non-fixing means are made active at the time of data retrieval operation, and the potential variation of said match line is positively corelated to that of said control word line.
Claim 9
Dependent Claim
16 words
A semiconductor integrated circuit according to claim 8, wherein said selective transistor is a unidirectional element.
Claim 10
Dependent Claim
25 words
A semiconductor integrated circuit according to claim 9, wherein said unidirectional element is what has a threshold voltage higher than that of any peripheral element.
Claim 11
Dependent Claim
233 words
A semiconductor integrated circuit comprising a plurality of retrieval memory word blocks, said block including a set of a memory cell having a first storage unit for defining the electrical connection and otherwise the non-connection between a first data line and a match line and a second storage unit for defining the electrical non-connection and otherwise the connection between a second data line and said match line, at least a selective transistor provided between at least one of said first and second storage units of the memory cell and said match line or between said first and second storage units and said first and second data lines, and a control word line for controlling said selective transistor, with said first data line, said second data line and said match line as those which are commonly used for said plurality of retrieval memory word blocks, and a potential detecting means for detecting an electric potential of said common match line connected to couplers of the first and second storage unit of the memory in the plurality of retrieval memory word blocks, said selective transistors therein or couplers of the selective transistors of the memory cells therein, control word line being used to effect connection and otherwise non-connection between each of said first and second data lines and said match line in accordance with the definition of connections of said first and second storage units.
Claim 12
Dependent Claim
22 words
A semiconductor integrated circuit according to claim 11, wherein said storage unit for defining the electrical connection is composed of a coupler.
Claim 13
Dependent Claim
19 words
A semiconductor integrated circuit according to claim 11, wherein said storage unit is composed of a nonvolatile memory element.
Claim 14
Dependent Claim
34 words
A semiconductor integrated circuit according to claim 11, wherein both said first and second storage units are composed of a nonvolatile memory element and each nonvolatile memory element is connected to each selective transistor.
Claim 15
Dependent Claim
21 words
A semiconductor integrated circuit according to claim 13 or 14, wherein said nonvolatile memory element is a MONOS-type nonvolatile memory element.
Claim 16
Dependent Claim
29 words
A semiconductor integrated circuit according to anyone of claims 11 to 15, wherein said match line further has fixing means for fixing an electric potential of said match line.
Claim 17
Dependent Claim
67 words
A semiconductor integrated circuit according to anyone of claims 11 to 16, wherein said control word line further has potential non-fixing means and connection means for connecting to said match line, said connection means and said potential non-fixing means are made active at the time of data retrieval operation, and the potential variation of said match line is positively corelated to that of said control word line.
Claim 18
Dependent Claim
69 words
A semiconductor integrated circuit according to anyone of claims 11 to 15, which further comprises a common connection line connected to couplers of the first and second storage units of the memory in the plurality of retrieval memory word blocks, said selective transistors therein or couplers of the selective transistors of the memory cells therein, and a unidirectional element provided between said common connection line and said match line.
Claim 19
Dependent Claim
23 words
A semiconductor integrated circuit according to claim 18, which further comprises fixing means for fixing an electric potential of said common connection line.
Claim 20
Dependent Claim
27 words
A semiconductor integrated circuit according to claim 18 or 19, wherein said unidirectional element is what has a threshold voltage higher than that of any peripheral element.
Claim 21
Dependent Claim
85 words
A semiconductor integrated circuit according to anyone of claims 11 to 15, which further comprises a common connection line connected to couplers of the first and second storage units of the memory in the plurality of retrieval memory word blocks, said selective transistors therein or couplers of the selective transistors of the memory cells therein, a control element provided between said common connection line and said match line, and a connection means for connecting the gate electrode of said control element to said match line.
Claim 22
Dependent Claim
22 words
A semiconductor integrated circuit according to claim 18, which further comprises fixing means for fixing an electric potential of said match line.
Claim 23
Dependent Claim
25 words
A semiconductor integrated circuit according to claim 21 or 22, wherein said control element have a threshold voltage higher than that of any peripheral element.
Claim 24
Dependent Claim
35 words
A semiconductor integrated circuit according to anyone of claims 11 to 23, which further comprises holding means for holding the result of detection made by said potential detecting means on each retrieval memory word block.
Claim 25
Dependent Claim
32 words
A semiconductor integrated circuit according to anyone of claims 11 to 24, which further comprises means for driving the respective control word lines of said retrieval memory word blocks in order predetermined.
Claim 26
Dependent Claim
159 words
A semiconductor integrated circuit comprising a memory cell including a first storage unit for defining the electrical connection and otherwise the non-connection between a first data line and a match line and a second storage unit for defining the electrical non-connection and otherwise the connection between a second data line and said match line, a control word line for controlling said first and second storage units in the memory cell, at least a selective transistor provided between said first and second storage units of the memory cell and said match line or between said first and second storage units and said first and second data lines, and a control line for controlling said selective transistor, said control word line and said control line being used to effect the connection and otherwise non-connection between each of said first and second data lines and said match line in accordance with the definition of connections of said first and second storage units.
Claim 27
Dependent Claim
19 words
A semiconductor integrated circuit according to claim 26, wherein said storage unit is composed of a nonvolatile memory element.
Claim 28
Dependent Claim
39 words
A semiconductor integrated circuit according to claim 26, wherein both said first and second storage units are composed of a nonvolatile memory element and a connection line of both said nonvolatile memory elements is connected to one selective transistor.
Claim 29
Dependent Claim
29 words
A semiconductor integrated circuit according to claim 27 or 28, wherein said nonvolatile memory element is at least one selected from the group consisting of EPROM, EEPROM and UVEPROM.
Claim 30
Dependent Claim
46 words
A semiconductor integrated circuit according to claim 26, wherein one of both said first and second storage units is a depression transistor, another of them is a enhancement transistor, and each said selective transistor is connected to each of the depression and enhancement transistors in series.
Claim 31
Dependent Claim
20 words
A semiconductor integrated circuit according to anyone of claims 26 to 30, wherein said selective transistor is a unidirectional element.
Claim 32
Dependent Claim
35 words
A semiconductor integrated circuit according to anyone of claims 26 to 30, which further comprises a unidirectional element provided between said match line and first and second storage units, coupler thereof or said selective transistor.
Claim 33
Dependent Claim
27 words
A semiconductor integrated circuit according to claim 31 or 32, wherein said unidirectional element is what has a threshold voltage higher than that of any peripheral element.
Claim 34
Dependent Claim
69 words
A semiconductor integrated circuit according to anyone of claims 26 to 30, wherein said control line of said selective transistor further has potential non-fixing means and connection means for connecting to said match line, said connection means and said potential non-fixing means are made active at the time of data retrieval operation, and the potential variation of said match line is positively corelated to that of said control line.
Claim 35
Dependent Claim
23 words
A semiconductor integrated circuit according to claim 34, wherein said selective transistor has a threshold voltage higher than that of any peripheral circuit.
Claim 36
Dependent Claim
30 words
A semiconductor integrated circuit according to anyone of claims 26 to 35, wherein said match line further has potential detecting means for detecting an electric potential of said match line.
Claim 37
Dependent Claim
29 words
A semiconductor integrated circuit according to anyone of claims 26 to 36, wherein said match line further has fixing means for fixing an electric potential of said match line.
Claim 38
Dependent Claim
165 words
A semiconductor integrated circuit comprising a plurality of retrieval memory word blocks, said block including a set of a memory cell having a first storage unit for defining the electrical connection and otherwise the non-connection between a first data line and a match line and a second storage unit for defining the electrical non-connection and otherwise the connection between a second data line and said match line and a control word line for controlling said first and second storage units in the memory cell, with said first data line, said second data line and said match line as those which are commonly used for said plurality of retrieval memory word blocks, and a potential detecting means for detecting an electric potential of said match line, said control word line being used to effect the connection and otherwise non-connection between each of said first and second data lines and said match line in accordance with the definition of connections of said first and second storage units.
Claim 39
Dependent Claim
84 words
A semiconductor integrated circuit according to claim 38, which further comprises at least one selective transistor provided between said match line and a coupler for coupling said first and second storage units and a control line for controlling said selective transistor, said control word line and control line being used to effect the connection and otherwise non-connection between each of said first and second data lines and said match line in accordance with the definition of connections of said first and second storage units.
Claim 40
Dependent Claim
21 words
A semiconductor integrated circuit according to claim 38 or 39, wherein said storage unit 13 composed of a nonvolatile memory element.
Claim 41
Dependent Claim
27 words
A semiconductor integrated circuit according to claim 40, wherein said nonvolatile memory element is at least one selected from the group consisting of EPROM, EEPROM and UVEPROM.
Claim 42
Dependent Claim
36 words
A semiconductor integrated circuit according to claim 38 or 39, wherein one of both said first and second storage units in the memory cell is a depression transistor and another of them is a enhancement transistor.
Claim 43
Dependent Claim
25 words
A semiconductor integrated circuit according to anyone of claims 38 to 42, wherein said match line further has fixing means for fixing an electric potential.
Claim 44
Dependent Claim
57 words
A semiconductor integrated circuit according to anyone of claims 39 to 42, which further comprises a common connection line connected to couplers of the first and second storage units of the memory in the plurality of retrieval memory word blocks,wherein said one selective transistor provided between one end of said common connection line and said match line.
Claim 45
Dependent Claim
23 words
A semiconductor integrated circuit according to claim 44, which further comprises fixing means for fixing an electric potential of said common connection line.
Claim 46
Dependent Claim
20 words
A semiconductor integrated circuit according to anyone of claims 39 to 45, wherein said selective transistor is a unidirectional element.
Claim 47
Dependent Claim
25 words
A semiconductor integrated circuit according to claim 46, wherein said unidirectional element is what has a threshold voltage higher than that of any peripheral element.
Claim 48
Dependent Claim
34 words
A semiconductor integrated circuit according to anyone of claims 39 to 44, wherein said control line of the selective transistor further has potential non-fixing means and connection means for connecting to said match line.
Claim 49
Dependent Claim
25 words
A semiconductor integrated circuit according to claim 48, wherein said selective transistor is what has a threshold voltage higher than that of any peripheral element.
Claim 50
Dependent Claim
71 words
A semiconductor integrated circuit according to anyone of claims 38 to 43, wherein said control word line of said selective transistor further has potential non-fixing means and connection means for connecting to said match line, said connection means and said potential non-fixing means are made active at the time of data retrieval operation, and the potential variation of said match line is positively corelated to that of said control word line.
Claim 51
Dependent Claim
35 words
A semiconductor integrated circuit according to anyone of claims 38 to 50, which further comprises holding means for holding the result of detection made by said potential detecting means on each retrieval memory word block.
Claim 52
Dependent Claim
32 words
A semiconductor integrated circuit according to anyone of claims 38 to 51, which further comprises means for driving the respective control word lines of said retrieval memory word blocks in order predetermined.
Claim 53
Dependent Claim
93 words
A semiconductor integrated circuit comprising a first transistor chain having a plurality of transistors connected in series, a first data line connected to one end of said first transistor chain, a match line connected to the other end of said first transistor chain, a second transistor chain having a plurality of transistors connected in series, a second data line connected to one end of said second transistor chain, said match line connected to the other end of said second transistor chain, potential detection means for detecting the electrical potential of said match line.
Claim 54
Dependent Claim
46 words
A semiconductor integrated circuit according to claim 53, which further comprises a selective transistor imposed between the other end of said first transistor chain and said match line, and a selective transistor interposed between the other end of said second transistor chain and said match line.
Claim 55
Dependent Claim
55 words
A semiconductor integrated circuit according to claim 53 or 54, wherein enhancement or depression transistors constitute said first and second transistor chains depending on the storage data and wherein an enhancement or depression transistor forms at least one of the transistors constituting said transistor chains as a chain control transistor, irrespective of said storage data.
Claim 56
Dependent Claim
47 words
A semiconductor integrated circuit according to claim 53 or 54, wherein nonvolatile transistors constitute the principal parts of said first and second transistor chains and wherein an enhancement or depression transistor forms at least one of the transistors constituting said transistor chains as a chain control transistor.
Claim 57
Dependent Claim
104 words
A semiconductor integrated circuit according to anyone of claims 53 to 56, which further comprises a plurality of word lines for driving respective gates from the outermost transistors among the transistors constituting said first and second transistor chains on one side toward the other side, said plurality of word lines being commonly used for said first and second transistor chains, and holding means for selectively holding the results of retrieval from said potential detection means, said holding means corresponding to control word lines other than what is used for controlling said chain control transistor out of said plurality of word lines for common use.
Claim 58
Dependent Claim
28 words
A semiconductor integrated circuit according to claim 57, which further comprises means for driving the respective control word lines of said retrieval memory word blocks in order predetermined.
Claim 59
Dependent Claim
20 words
A semiconductor integrated circuit according to anyone of claims 54 to 58, wherein said selective transistor is a unidirectional element.
Claim 60
Dependent Claim
29 words
A semiconductor integrated circuit according to claim 59, which further comprises fixing means for fixing electric potentials of said other ends of said first and second transistor chains, respectively.
Claim 61
Dependent Claim
27 words
A semiconductor integrated circuit according to claim 59 or 60, wherein said unidirectional element is what has a threshold voltage higher than that of any peripheral element.
Claim 62
Dependent Claim
45 words
A semiconductor integrated circuit according to anyone of claims 54 to 58, which further comprises connection means for connecting said match line to one control line connecting to the gate electrodes of said two selective transistor connected to said first and second selective transistor chains.
Claim 63
Dependent Claim
35 words
A semiconductor integrated circuit according to claim 62, wherein said selective transistors connected to the other ends of said first and second transistor chains have a threshold voltage higher than that of any peripheral circuit.
Claim 64
Dependent Claim
96 words
A semiconductor integrated circuit according to claim 53, wherein said control line for connecting both gate electrodes of at least one chain control transistor included in transistors constituting said first transistor chain and at least one chain control transistor included in transistors constituting said second transistor chain further has potential non-fixing means and connection means for connecting to said match line, said connection means and said potential non-fixing means are made active at the time of data retrieval operation, and the potential variation of said match line is positively corelated to that of said control line.
Claim 65
Dependent Claim
25 words
A semiconductor integrated circuit according to claim 64, wherein enhancement or depression transistors constitute said first and second transistor chains depending on the storage data.
Claim 66
Dependent Claim
22 words
A semiconductor integrated circuit according to claim 64, wherein nonvolatile transistors constitute the principal parts of said first and second transistor chains.
Claim 67
Dependent Claim
104 words
A semiconductor integrated circuit according to anyone of claims 64 to 66, which further comprises a plurality of word lines for driving respective gates from the outermost transistors among the transistors constituting said first and second transistor chains on one side toward the other side, said plurality of word lines being commonly used for said first and second transistor chains, and holding means for selectively holding the results of retrieval from said potential detection means, said holding means corresponding to control word lines other than what is used for controlling said chain control transistor out of said plurality of word lines for common use.
Claim 68
Dependent Claim
28 words
A semiconductor integrated circuit according to claim 67, which further comprises means for driving the respective control word lines of said retrieval memory word blocks in order predetermined.
Claim 69
Dependent Claim
29 words
A semiconductor integrated circuit according to anyone of claims 62 to 68, wherein said match line further has fixing means for fixing an electric potential of said match line.
Claim 70
Dependent Claim
88 words
A semiconductor integrated circuit comprising a first transistor, a first signal line connected to one of source and drain electrodes of said first transistor, connection control means for controlling the electrical connection and otherwise the non-connection between a first signal and a control word line connected to a gate electrode of the first transistor, potential non-fixing means for non-fixing said control word line, wherein said potential non-fixing means and said connection control means are made active, and said first transistor is caused to function as a unidirectional element.
References Cited (Backward Citations)
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