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US4805139A Expired / Lapsed US ⏱️ 0.0 years remaining

Propagating FIFO storage device

Assignee: RPX Corp
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Filing: 1987-10-22
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Granted: 1989-02-14
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Expires: 2007-10-22
📄 Original PDF 🌐 Google Patents

Abstract

Abstract A propagating first-in, first-out (FIFO) storage device is driven by a two-phase non-overlapping clock and includes a plurality of storage cells (C1, . . . C4) and a plurality of tracking bit cell circuits (T1, . . . T4). Each of the storage cells includes first pass gate transistors (G1, . . . G8), first inverters (INV1, . . . INV8), second pass gate transistors (G9, . . . G16), and second inverters (INV9, . . . INV16). The first pass gate transistors are responsive to a control signal from the tracking circuit for loading data input signals into the first inverter means. The second pass gate transistors are responsive to a first phase of the clock for shifting the data input signals into the second inverters.

Inventors

  • 👤 David Norris

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 04:28
CPC Classifications
G; G06; G06F; G06F5/00; G06F5/06; G06F5/08; G11; G11C; G11C19/00; G11C19/28

Claims Analysis

Total Claims: 23
Claim 1
Independent Claim 241 words
A propagating first-in, first-out (FIFO) storage device, said storage device being driven by a two-phase non-overlapping clock, said storage device comprising: a plurality of n-bit storage cells (C1, . . . C4) arranged in a push-down stack, each of said storage cells including first pass gate means, first inverter means, second pass gate means, and second inverter means for storing an n-bit data word and for generating outputs corresponding to said stored n-bit data word; said first pass gate means having inputs and outputs, said first inverter means having inputs coupled to the corresponding outputs of said first pass gate means and outputs, said second pass gate means having inputs coupled to the corresponding outputs of said first inverter means and outputs, and said second inverter means having inputs coupled to the corresponding outputs of said second pass gate means and outputs for generating the outputs corresponding to said n-bit data word; data input nodes for coupling data input signals to the inputs of said first pass gate means; said first pass gate means being responsive to a control signal for loading said data input signal into said first inverter means; said second pass gate means being responsive to a first phase of said clock for shifting said data into said second inverter means; and a plurality of tracking bit cell circuits (T1, ...T4) responsive to a load signal and a second phase of said clock for generating said control signals.
Claim 2
Dependent Claim 241 words
A propagating first-in, first-out (FIFO) storage device, said storage device being driven by a two-phase non-overlapping clock, said storage device comprising: a plurality of n-bit storage cells (C1, . . . C4) arranged in a push-down stack, each of said storage cells including first pass gate means, first inverter means, second pass gate means, and second inverter means for storing an n-bit data word and for generating outputs corresponding to said stored n-bit data word; said first pass gate means having inputs and outputs, said first inverter means having inputs coupled to the corresponding outputs of said first pass gate means and outputs, said second pass gate means having inputs coupled to the corresponding outputs of said first inverter means and outputs, and said second inverter means having inputs coupled to the corresponding outputs of said second pass gate means and outputs for generating the outputs corresponding to said n-bit data word; data input nodes for coupling data input signals to the inputs of said first pass gate means; said first pass gate means being responsive to a control signal for loading said data input signal into said first inverter means; said second pass gate means being responsive to a first phase of said clock for shifting said data into said second inverter means; and a plurality of tracking bit cell circuits (T1, ...T4) responsive to a load signal and a second phase of said clock for generating said control signals.
Claim 3
Dependent Claim 25 words
A propagating FIFO storage device as claimed in claim 1, wherein said first pass gate means comprises a plurality of first N-channel transistors (G1A, ...G8A).
Claim 4
Dependent Claim 23 words
A propagating FIFO storage device as claimed in claim 2, wherein said first inverter means comprises a plurality of first inverters (INV1A, ...INV8A).
Claim 5
Dependent Claim 25 words
A propagating FIFO storage device as claimed in claim 3, wherein said second pass gate means comprises a plurality of second N-channel transistors (G9A, ...G16A).
Claim 6
Dependent Claim 23 words
A propagating FIFO storage device as claimed in claim 4, wherein said second inverter means comprises a plurality of second inverters (INV9A, ...INV16A).
Claim 7
Dependent Claim 62 words
A propagating FIFO storage device as claimed in claim 5, wherein each of said plurality of first N-channel transistors (G1A, ...G8A) has a corresponding drain electrode coupled to one of the respective data input nodes, a corresponding source electrode coupled to one of the respective inputs of said first inverters (INV1A, ...INV8A), and a corresponding gate electrode coupled to the control signal.
Claim 8
Dependent Claim 69 words
A propagating FIFO storage device as claimed in claim 6, wherein each of said plurality of second N-channel transistors (G9A, ...G16A) has a corresponding drain electrode coupled to one of the respective outputs of said first inverters (INV1A, ...INV8A), a corresponding source electrode coupled to one of the respective inputs of said second inverters (INV9A, ...INV16A), and a corresponding gate electrode coupled to the first phase of said clock.
Claim 9
Dependent Claim 46 words
A propagating FIFO storage device as claimed in claim 7, wherein each of said tracking bit cell circuits (T1, ...T4) include an AND logic gate means (A1A, ...A1D), third, fourth and fifth inverters (I1, I2, I3), and third, fourth and fifth N-channel transistors (N1, N2, N3).
Claim 10
Dependent Claim 63 words
A propagating FIFO storage device as claimed in claim 8, wherein said logic gate means comprises a three-input AND logic gate (A1) which has a first input coupled to the load signal, a second input coupled to the first phase of said clock, a third input coupled to the output of said fifth inverter (I3), and an output for generating the control signal.
Claim 11
Dependent Claim 159 words
A propagating FIFO storage device as claimed in claim 9, wherein said output of said logic gate (A1) is coupled to the gate of said third N-channel transistor (N1), said third N-channel transistor (N1) having its drain coupled to the load signal and its source coupled to the input of said fifth inverter (I3) and to the drain of said fourth N-channel transistor (N2), said fourth N-channel transistor (N2) having its source coupled to a ground potential and its gate coupled to a second control signal, the output of said fifth inverter (I3) being coupled to the drain of said fifth N-channel transistor (N3), the gate of said fifth N-channel transistor (N3) being coupled to the first phase of said clock and its source coupled to the input of said fourth inverter (I2), the output of said fourth inverter defining the output of said tracking bit cell circuit and being coupled to the input of said third inverter (I1).
Claim 12
Dependent Claim 35 words
A propagating FIFO storage device as claimed in claim 10, wherein said second control signal is defined by the output of said AND logic gate (A1) in the next higher storage cell in the stack.
Claim 13
Dependent Claim 33 words
A propagating FIFO storage device as claimed in claim 11, wherein the outputs (16) of said tracking circuits (T1, ...T4) defines the load signal for the next higher storage cell in the stack.
Claim 14
Dependent Claim 57 words
A propagating FIFO storage device as claimed in claim 12, further comprising a second AND logic gate (A2) which has a first input coupled to the first phase of the clock and a second input coupled to a read signal, and an output for generating the second control signal for the highest storage cell in the stack.
Claim 15
Dependent Claim 39 words
A propagating FIFO storage device as claimed in claim 8, wherein each of said tracking bit cell circuits (T1, ...T4) include a P-channel feedback transistor (P1FA, ...P1FD), a feedback inverter (I3FA, ...I3FD), and an N-channel reset transistor (NRA, ...NRD).
Claim 16
Dependent Claim 32 words
A propagating FIFO storage device as claimed in claim 7, wherein each of said storage cells (C1, ...C4) includes a plurality of feedback inverters (INVF1A...INVF8A) and a plurality of feedback transistors (GF9A...Gf16A).
Claim 17
Dependent Claim 46 words
A propagating FIFO storage device as claimed in claim 1, wherein each of said tracking bit cell circuits (T1, ...T4) include an AND logic gate means (A1A, ...A1D), first, second and third inverters (I1, I2, I3), and first, second and third N-channel transistors (N1, N2, N3).
Claim 18
Dependent Claim 63 words
A propagating FIFO storage device as claimed in claim 16, wherein said logic gate means comprises a three-input AND logic gate (A1) which has a first input coupled to the load signal, a second input coupled to the first phase of said clock, a third input coupled to the output of said third inverter (I3), and an output for generating the control signal.
Claim 19
Dependent Claim 160 words
A propagating FIFO storage device as claimed in claim 17, wherein said output of said logic gate (A1) is coupled to the gate of said first N-channel transistor (N1), said first N-channel transistor (N1) having its drain coupled to the load signal and its source coupled to the input of said third inverter (I3) and to the drain of said second N-channel transistor (N2), said second N-channel transistor (N2) having its source coupled to a ground potential and its gate coupled to a second control signal, the output of said third inverter (I3) being coupled to the drain of said third N-channel transistor (N3), the gate of said third N-channel transistor (N3) being coupled to the first phase of said clock signal and its source coupled to the input of said second inverter (I2), the output of said second inverter defining the output of said tracking bit cell circuit and being coupled to the input of said first inverter (I1).
Claim 20
Dependent Claim 35 words
A propagating FIFO storage device as claimed in claim 18, wherein said second control signal is defined by the output of said AND logic gate (A1) in the next higher storage cell in the stack.
Claim 21
Dependent Claim 33 words
A propagating FIFO storage device as claimed in claim 19, wherein the outputs (16) of said tracking circuits (T1, ...T4) defines the load signal for the next higher storage cell in the stack.
Claim 22
Dependent Claim 57 words
A propagating FIFO storage device as claimed in claim 20, further comprising a second AND logic gate (A2) which has a first input coupled to the first phase of the clock and a second input coupled to a read signal, and an output for generating the second control signal for the highest storage cell in the stack.
Claim 23
Dependent Claim 41 words
A propagating FIFO storage device as claimed in claim 21, wherein the outputs of said second inverters (INV9D, ...INV16D) in the highest storage cell (C4) are coupled to the data output nodes (D9A, ...D16A) for generating data output signals (D01, ...D08).

References Cited (Backward Citations)

US4151609A Cited
US4390970A Cited
US4409680A Cited
US4733376A Cited
US4651333A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-02-14 1992-08-15 1993-02-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-02-14 1996-08-15 1997-02-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-02-14 2000-08-15 2001-02-14 $7700.00 Window Closed / Lapsed

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