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US4891794A Expired / Lapsed US ⏱️ 0.0 years remaining

Three port random access memory

Assignee: Micron Technology Inc
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Filing: 1988-06-20
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Granted: 1990-01-02
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Expires: 2008-06-20
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Abstract

Abstract A three port memory device has two serial ports and a random access memory port. The random access memory port is addressed to a random access memory in a conventional manner, using RAS and CAS address signals. Data may also be supplied and retrieved through two serial ports to a pair of serial access memories for transfer between the serial ports and the random access memory. This configuration permits formatted data to be simultaneously assessed through the two serial ports, while the random access memory port is being accessed.

Inventors

  • 👤 Glen E. Hush
  • 👤 Jeffrey S. Mailloux
  • 👤 Eugene H. Cloud

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 06:44
CPC Classifications
G; G11; G11C; G11C7/00; G11C7/10; G11C7/1075

Claims Analysis

Total Claims: 22
Claim 1
Independent Claim 140 words
Solid state memory device capable of receiving and transmitting data in a serial format and permitting random access to the data, characterized by: (a) a random access memory array containing a plurality of data bits; (b) a plurality of serial access memories; (c) transfer circuitry including a plurality of transfer gates communicating with the random access memory array, the transfer circuitry communicating between the transfer gates and the serial access memories in order to transfer data between the random access memory and the serial access memories; (d) the transfer circuitry transferring said data selectively to any one of said plurality of serial access memories; (e) the transfer circuitry including a transfer control circuit controlling with which serial access memory said transfer of data is performed; and (f) a serial address connection for at least two of the serial access memories.
Claim 2
Dependent Claim 140 words
Solid state memory device capable of receiving and transmitting data in a serial format and permitting random access to the data, characterized by: (a) a random access memory array containing a plurality of data bits; (b) a plurality of serial access memories; (c) transfer circuitry including a plurality of transfer gates communicating with the random access memory array, the transfer circuitry communicating between the transfer gates and the serial access memories in order to transfer data between the random access memory and the serial access memories; (d) the transfer circuitry transferring said data selectively to any one of said plurality of serial access memories; (e) the transfer circuitry including a transfer control circuit controlling with which serial access memory said transfer of data is performed; and (f) a serial address connection for at least two of the serial access memories.
Claim 3
Dependent Claim 28 words
Solid state memory device as described in claim 1, further characterized by: the random access memory array being addressable by external read commands and by external write commands.
Claim 4
Dependent Claim 32 words
Solid state memory device as described in claim 2, further characterized by: the serial address memories being static or dynamic memory circuits which are each addressed in at least one static sequence.
Claim 5
Dependent Claim 25 words
Solid state memory device as described in claim 3, further characterized by: the random access memory array being addressable by RAS and CAS address commands.
Claim 6
Dependent Claim 40 words
Solid state memory device as described in claim 4, further characterized by: (a) the memory device being incorporated onto a single portion of a semiconductor wafer; and (b) the random access memory array being a dynamic random access memory array.
Claim 7
Dependent Claim 46 words
Solid state memory device as described in claim 2, further characterized by: the transfer circuitry communicating between the transfer gates and the serial access memories in order to transfer data between the random access memory and any one of a plurality of the serial access memories;
Claim 8
Dependent Claim 30 words
Solid state memory device as described in claim 6, further characterized by: each serial access memory including a plurality of multiple bit memories, each of which plurality is separately addressable.
Claim 9
Dependent Claim 29 words
Solid state memory device as described in claim 2, further characterized by: the serial address memories being dynamic memory circuits which are each addressed in at least one sequence.
Claim 10
Dependent Claim 30 words
Solid state memory device as described in claim 1, further characterized by: each serial access memory including a plurality of multiple bit memories, each of which plurality is separately addressable.
Claim 11
Dependent Claim 40 words
Solid state memory device as described in claim 1, further characterized by: (a) the memory device being incorporated onto a single portion of a semiconductor wafer; and (b) the random access memory array being a dynamic random access memory array.
Claim 12
Dependent Claim 40 words
Solid state memory device as described in claim 1, further characterized by: (a) the memory device being incorporated onto a single portion of a semiconductor wafer; and (b) the random access memory array being a static random access memory array.
Claim 13
Dependent Claim 70 words
Solid state memory device as described in claim 1, further characterized by: the serial address memories each being registers having like number of bits; the serial address memories each having independent enable inputs; the serial address memories each being responsive to a directional control signal; and the transfer of said data being accomplished when a transfer enable signal and the directional control signal are applied to the serial address memory.
Claim 14
Dependent Claim 148 words
Solid state memory device capable of receiving and transmitting data in a serial format and permitting random access to the data, characterized by: (a) a random access memory array containing a plurality of data bits, (b) a plurality of serial access memories; (c) the random access memory array being addressable by external read commands and by external write commands; (d) the serial address memories being static memory circuits which are each addressed in at least one static sequence; (e) a plurality of transfer gates communicating with the random access memory array and the serial access memories in order to transfer data between the random access memory and one of the serial access memories; (f) the plurality of transfer gates transferring said data selectively to any one of said plurality of serial access memories; and (g) a serial address connection for at least two of the serial access memories.
Claim 15
Dependent Claim 148 words
Solid state memory device capable of receiving and transmitting data in a serial format and permitting random access to the data, characterized by: (a) a random access memory array containing a plurality of data bits, (b) a plurality of serial access memories; (c) the random access memory array being addressable by external read commands and by external write commands; (d) the serial address memories being static memory circuits which are each addressed in at least one static sequence; (e) a plurality of transfer gates communicating with the random access memory array and the serial access memories in order to transfer data between the random access memory and one of the serial access memories; (f) the plurality of transfer gates transferring said data selectively to any one of said plurality of serial access memories; and (g) a serial address connection for at least two of the serial access memories.
Claim 16
Dependent Claim 25 words
Solid state memory device as described in claim 13, further characterized by: the random access memory array being addressable by RAS and CAS address commands.
Claim 17
Dependent Claim 40 words
Solid state memory device as described in claim 14, further characterized by: (a) the memory device being incorporated onto a single portion of a semiconductor wafer; and (b) the random access memory array being a dynamic random access memory array.
Claim 18
Dependent Claim 29 words
Solid state memory device as described in claim 13, further characterized by: the serial address memories being dynamic memory circuits which are each addressed in at least one sequence.
Claim 19
Dependent Claim 40 words
Solid state memory device as described in claim 13, further characterized by: (a) the memory device being incorporated onto a single portion of a semiconductor wafer; and (b) the random access memory array being a dynamic random access memory array.
Claim 20
Dependent Claim 40 words
Solid state memory device as described in claim 13, further characterized by: (a) the memory device being incorporated onto a single portion of a semiconductor wafer; and (b) the random access memory array being a static random access memory array.
Claim 21
Dependent Claim 30 words
Solid state memory device as described in claim 13, further characterized by: each serial access memory including a plurality of multiple bit memories, each of which plurality is separately addressable.
Claim 22
Dependent Claim 70 words
Solid state memory device as described in claim 13, further characterized by: the serial address memories each being registers having like number of bits; the serial address memories each having independent enable inputs; the serial address memories each being responsive to a directional control signal; and the transfer of said data being accomplished when a transfer enable signal and the directional control signal are applied to the serial address memory.

References Cited (Backward Citations)

US4120048A Cited
US4646270A Cited
US4747081A Cited
US4648077A Cited
US4794566A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-01-01 1993-07-03 1994-01-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-01-01 1997-07-03 1998-01-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-01-01 2001-07-03 2002-01-02 $7700.00 Window Closed / Lapsed

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