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US6034544A Expired / Lapsed US ⏱️ 0.0 years remaining

Programmable input/output block (IOB) in FPGA integrated circuits

Assignee: Lattice Semiconductor Corp
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Filing: 1997-12-22
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Granted: 2000-03-07
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Expires: 2017-12-22
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Abstract

Abstract A Field Programmable Gate Array (FPGA) device includes a plurality of input/output blocks (IOBs) and variable grain blocks (VGBs) An inter-connect network provides routing of signals between the IOBs and VGBs. The VGBs include a plurality of L-organized CBBs (configurable logic blocks) having function-producing resources. The IOBs are arranged along a top, left, bottom and right side of the plurality of VGBs. An IOB includes a 1) delay for timing input signals, 2) a configurable output latch which may be set or reset responsive to control signals, and 3) transistor for controlling a NOR line. The IOB is programmably configured to the inter-connect network which includes vertical and horizontal inter-connect channels comprising adjacent inter-connect lines.

Inventors

  • 👤 Om P. Agrawal
  • 👤 Herman M. Chang
  • 👤 Bradley A. Sharpe-Geisler
  • 👤 Bai Nguyen

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 20:13
CPC Classifications
H; H03; H03K; H03K19/00; H03K19/02; H03K19/173; H03K19/177; H03K19/17736; H03K19/17744

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 76 words
An input/output block (IOB) for a field programmable gate array (FPGA) device, comprising: (a) an input for receiving an input signal from a pin; (b) a register/latch, coupled to the input, having an output, for providing an output signal; and (c) a first transistor, coupled to the register/latch output, for providing a ground path for an inter-connect resource coupled to the IOB, wherein the inter-connect resource is coupled to a second IOB and a current source.
Claim 2
Dependent Claim 76 words
An input/output block (IOB) for a field programmable gate array (FPGA) device, comprising: (a) an input for receiving an input signal from a pin; (b) a register/latch, coupled to the input, having an output, for providing an output signal; and (c) a first transistor, coupled to the register/latch output, for providing a ground path for an inter-connect resource coupled to the IOB, wherein the inter-connect resource is coupled to a second IOB and a current source.
Claim 3
Dependent Claim 21 words
The IOB of claim 1, wherein the inter-connect resource is a line positioned substantially parallel to a side of the FPGA.
Claim 4
Dependent Claim 15 words
The IOB of claim 1, wherein a second transistor is coupled to the first transistor.
Claim 5
Dependent Claim 28 words
The IOB of claim 3, wherein the second transistor includes a gate coupled to a multiplexer and the first transistor includes a gate coupled to the register/latch output.
Claim 6
Dependent Claim 204 words
An input/output block (IOB) for a field programmable gate array (FPGA) device, comprising: (a) an input for receiving an input signal from a pin; (b) a delay element, coupled to the input, having an output for providing a delayed input signal; (c) a first multiplexer, coupled to the delay element, having an output for providing a first multiplexer signal responsive to the delayed input signal; (d) a second multiplexer, coupled to the first multiplexer, having an output for providing a second multiplexer signal responsive to the first multiplexer signal; (e) a register/latch, coupled to the second multiplexer, having an output for providing a register/latch output signal responsive to the second multiplexer signal, a set signal and a reset signal; (f) a set/reset line for providing a set/reset signal; (g) a decoder, coupled to the set/reset line, for providing the set signal or the reset signal responsive to the set/reset signal; (h) a third multiplexer, coupled to the register/latch output, having an output for providing a third multiplexer signal responsive to the register/latch output signal; and, (i) an amplifier, coupled to the third multiplexer, having an output for providing an amplified signal to an inter-connect resource in the FPGA responsive to the third multiplexer signal.
Claim 7
Dependent Claim 204 words
An input/output block (IOB) for a field programmable gate array (FPGA) device, comprising: (a) an input for receiving an input signal from a pin; (b) a delay element, coupled to the input, having an output for providing a delayed input signal; (c) a first multiplexer, coupled to the delay element, having an output for providing a first multiplexer signal responsive to the delayed input signal; (d) a second multiplexer, coupled to the first multiplexer, having an output for providing a second multiplexer signal responsive to the first multiplexer signal; (e) a register/latch, coupled to the second multiplexer, having an output for providing a register/latch output signal responsive to the second multiplexer signal, a set signal and a reset signal; (f) a set/reset line for providing a set/reset signal; (g) a decoder, coupled to the set/reset line, for providing the set signal or the reset signal responsive to the set/reset signal; (h) a third multiplexer, coupled to the register/latch output, having an output for providing a third multiplexer signal responsive to the register/latch output signal; and, (i) an amplifier, coupled to the third multiplexer, having an output for providing an amplified signal to an inter-connect resource in the FPGA responsive to the third multiplexer signal.

References Cited (Backward Citations)

US5260881A Cited
US5210448A Cited
US5365125A Cited
US5581199A Cited
US5594367A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2003-03-07 2003-09-06 2004-03-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2007-03-07 2007-09-06 2008-03-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2011-03-07 2011-09-06 2012-03-07 $7700.00 Window Closed / Lapsed

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