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US4567577A Expired / Lapsed US ⏱️ 0.0 years remaining

Impedance modulated CMOS RAM cell

Assignee: Texas Instruments Inc
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Filing: 1982-11-04
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Granted: 1986-01-28
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Expires: 2002-11-04
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Abstract

Abstract A random access memory cell of complementary field effect transistors that include a bit storage latch for storing binary bit information connected to a word address line and a data address line. The data address line provides bit information to the latch. This bit data is stored in the latch when the word address line is active. A switching circuit is connected to the latch that enables new data to be stored in the latch by removing the previously stored data during the time that the new data is being stored.

Inventors

  • 👤 Arthur B. Oliver

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 11:05
CPC Classifications
G; G11; G11C; G11C11/00; G11C11/21; G11C11/34; G11C11/40; G11C11/41; G11C11/412; G11C11/413; G11C11/417; G11C11/419

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 100 words
A random access memory cell of complementary field effect transistors comprising: a latch for storing bit information connected to a word address line and a data line to receive bit information from said data line when said word address line is active, said latch including first and second inverter circuits, each of said inverter circuits having an output coupled to the input of the other inverter circuit; switching means connected to said latch for enablng new data information to be stored in said latch by disabling a portion of each of said first and second inverter circuits of said latch.
Claim 2
Dependent Claim 100 words
A random access memory cell of complementary field effect transistors comprising: a latch for storing bit information connected to a word address line and a data line to receive bit information from said data line when said word address line is active, said latch including first and second inverter circuits, each of said inverter circuits having an output coupled to the input of the other inverter circuit; switching means connected to said latch for enablng new data information to be stored in said latch by disabling a portion of each of said first and second inverter circuits of said latch.
Claim 3
Dependent Claim 77 words
A random access memory cell according to claim 1 wherein said first inverter circuit includes a first n-channel field effect transistor and a first p-channel field effect transistor, said second inverter circuit includes a second n-channel field effect transistor and a second p-channel field effect transistor and said switching means being connected to said first and second n-channel field effect transistors to disable said first and second n-channel field effect transistors during storage of new data information.
Claim 4
Dependent Claim 255 words
A random access memory cell of complementary field effect devices comprising: a latch circuit for storing bit information by assuming one of two stable states including (1) a first inverter circuit including a pair of complementary field effect devices having a first input connected to a first node and a first output connected to a second node and (2) a second inverter circuit including a pair of complementary field effect devices having a second input connected to said second node and a second output connected to said first node, said latch circuit operating whereby said first and second inverter circuits assume opposite states; a word address line having an active signal thereon upon selection of said latch circuit; a data line having a data signal to be written into said memory cell thereon upon selection of said latch circuit; a data complement line having the complement of said data signal thereon upon selection of said latch circuit; a first write drive field effect device having a source connected to said data line, a drain connected to said first node of said latch circuit and a gate connected to said word address line; a second write drive field effect device having a source connected to said data complement line, a drain connected to said second node of said latch circuit and a gate connected to said word address line; and a switching means connected to said latch circuit for disabling a portion of said first and second inverter circuits to enable writing into said latch circuit.
Claim 5
Dependent Claim 255 words
A random access memory cell of complementary field effect devices comprising: a latch circuit for storing bit information by assuming one of two stable states including (1) a first inverter circuit including a pair of complementary field effect devices having a first input connected to a first node and a first output connected to a second node and (2) a second inverter circuit including a pair of complementary field effect devices having a second input connected to said second node and a second output connected to said first node, said latch circuit operating whereby said first and second inverter circuits assume opposite states; a word address line having an active signal thereon upon selection of said latch circuit; a data line having a data signal to be written into said memory cell thereon upon selection of said latch circuit; a data complement line having the complement of said data signal thereon upon selection of said latch circuit; a first write drive field effect device having a source connected to said data line, a drain connected to said first node of said latch circuit and a gate connected to said word address line; a second write drive field effect device having a source connected to said data complement line, a drain connected to said second node of said latch circuit and a gate connected to said word address line; and a switching means connected to said latch circuit for disabling a portion of said first and second inverter circuits to enable writing into said latch circuit.
Claim 6
Dependent Claim 83 words
A random access memory cell of complementary field effect devices as claimed in claim 3, wherein: said first inverter circuit includes a first n-channel field effect device and a first p-channel field effect device; said second inverter circuit includes a second n-channel field effect device and a second p-channel field effect device; and said switching means is connected to said first and second n-channel field effect devices to disable said first and second n-channel field effect devices upon writing into said latch circuit.

References Cited (Backward Citations)

US3968479A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-01-27 1989-07-29 1990-01-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-01-27 1993-07-29 1994-01-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-01-27 1997-07-29 1998-01-28 $7700.00 Window Closed / Lapsed

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