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US7389456B2 Expired / Lapsed US ⏱️ 0.0 years remaining

IC with linking module in series with TAP circuitry

Assignee: Texas Instruments Inc
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Filing: 2006-04-12
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Granted: 2008-06-17
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Expires: 2026-04-12
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Abstract

Abstract IEEE 1149.1 Test Access Ports (TAPs) may be utilized at both IC and intellectual property core design levels. TAPs serve as serial communication ports for accessing a variety of embedded circuitry within ICs and cores including; IEEE 1149.1 boundary scan circuitry, built in test circuitry, internal scan circuitry, IEEE 1149.4 mixed signal test circuitry, IEEE P5001 in-circuit emulation circuitry, and IEEE P1532 in-system programming circuitry. Selectable access to TAPs within ICs is desirable since in many instances being able to access only the desired TAP(s) leads to improvements in the way testing, emulation, and programming may be performed within an IC. A TAP linking module is described that allows TAPs embedded within an IC to be selectively accessed using 1149.1 instruction scan operations.

Inventors

  • 👤 Lee D. Whetsel
  • 👤 Baher S. Haroun
  • 👤 Brian J. Lasher
  • 👤 Anjali Kinra

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 14:18
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/28; G01R31/317; G01R31/3177; G01R31/3181; G01R31/3185; G01R31/318533; G01R31/318555; G01R31/31727

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 151 words
An integrated circuit comprising: A. first TAP circuitry having a test data input, a test data output, a test clock input, and a test mode select input; B. second TAP circuitry having a test data input, a test data output, a test clock input, and a test mode select input; C. input linking circuitry selectively coupling test data input signals and test mode select signals to the first and second TAP circuitry in response to linking control signal inputs; D. output linking circuitry selectively coupling test data output signals from the first and second TAP circuitry in response to linking control signal inputs; and E. TAP linking module circuitry coupled in series with the test data inputs and test data outputs of the first and second TAP circuitry and having linking control signal outputs connected to the linking control signal inputs of the input linking circuitry and the output linking circuitry.
Claim 2
Dependent Claim 151 words
An integrated circuit comprising: A. first TAP circuitry having a test data input, a test data output, a test clock input, and a test mode select input; B. second TAP circuitry having a test data input, a test data output, a test clock input, and a test mode select input; C. input linking circuitry selectively coupling test data input signals and test mode select signals to the first and second TAP circuitry in response to linking control signal inputs; D. output linking circuitry selectively coupling test data output signals from the first and second TAP circuitry in response to linking control signal inputs; and E. TAP linking module circuitry coupled in series with the test data inputs and test data outputs of the first and second TAP circuitry and having linking control signal outputs connected to the linking control signal inputs of the input linking circuitry and the output linking circuitry.
Claim 3
Dependent Claim 28 words
The integrated circuit of claim 1 in which the TAP linking module circuitry is free of any connection of control signals from the first and second TAP circuitry.
Claim 4
Dependent Claim 94 words
The integrated circuit of claim 1 in which the first and second TAP circuitry each include: i. a TAP controller connected to the test clock input and the test mode select input and having control outputs; ii. an instruction register coupled to the test data input, the test data output, and the control outputs, and having instruction outputs; iii. a data register coupled to the test data input, the test data output, and the instruction outputs; and iv. multiplexer circuitry coupling the test data output to the instruction register and to the data register.
Claim 5
Dependent Claim 16 words
The integrated circuit of claim 1 in which the first TAP circuitry includes boundary scan circuitry.
Claim 6
Dependent Claim 37 words
The integrated circuit of claim 1 in which the input linking circuitry includes gating circuitry selectively coupling the test mode select signals to the first and second TAP circuitry in response to the linking control signal inputs.
Claim 7
Dependent Claim 55 words
The integrated circuit of claim 1 in which the input linking circuitry includes multiplexing circuitry selectively coupling the test data input signals to the first and second TAP circuitry and selectively coupling the test data output signal from the second TAP circuitry to the first TAP circuitry in response to the linking control signal inputs.
Claim 8
Dependent Claim 41 words
The integrated circuit of claim 1 in which the output linking circuitry includes multiplexing circuitry selectively coupling the test data outputs of the first and second TAP circuitry to the TAP linking module circuitry in response to linking control signal inputs.
Claim 9
Dependent Claim 389 words
An integrated circuit comprising: A. first TAP circuitry having a test data input, a test data output, a test clock input, and a test mode select input, the first TAP circuitry including: i. a TAP controller connected to the test clock input and the test mode select input and having control outputs; ii. an instruction register coupled to the test data input, the test data output, and the control outputs, and having instruction outputs; iii. a data register coupled to the test data input, the test data output, and the instruction outputs; and iv. multiplexer circuitry coupling the test data output to the instruction register and to the data register; B. second TAP circuitry having a test data input, a test data output, a test clock input, and a test mode select input, the second TAP circuitry including: i. a TAP controller connected to the test clock input and the test mode select input and having control outputs; ii. an instruction register coupled to the test data input, the test data output, and the control outputs, and having instruction outputs; iii. a data register coupled to the test data input, the test data output, and the instruction outputs; and iv. multiplexer circuitry coupling the test data output to the instruction register and to the data register; C. input linking circuitry including multiplexing circuitry selectively coupling test data input signals to the first and second TAP circuitry and selectively coupling the test data output signal from the second TAP circuitry to the first TAP circuitry in response to linking control signal inputs, the input linking circuitry including gating circuitry selectively coupling test mode select signals to the first and second TAP circuitry in response to the linking control signal inputs; D. output linking circuitry including multiplexing circuitry selectively coupling the test data outputs of the first and second TAP circuitry to a test data output lead in response to the linking control signal inputs; and E. TAP linking module circuitry coupled in series with the test data inputs and outputs of the first and second TAP circuitry and having linking control signal outputs connected to the linking control signal inputs of the input linking circuitry and the output linking circuitry, the TAP linking module circuitry being free of any connection of control signals from the first and second TAP circuitry.
Claim 10
Dependent Claim 389 words
An integrated circuit comprising: A. first TAP circuitry having a test data input, a test data output, a test clock input, and a test mode select input, the first TAP circuitry including: i. a TAP controller connected to the test clock input and the test mode select input and having control outputs; ii. an instruction register coupled to the test data input, the test data output, and the control outputs, and having instruction outputs; iii. a data register coupled to the test data input, the test data output, and the instruction outputs; and iv. multiplexer circuitry coupling the test data output to the instruction register and to the data register; B. second TAP circuitry having a test data input, a test data output, a test clock input, and a test mode select input, the second TAP circuitry including: i. a TAP controller connected to the test clock input and the test mode select input and having control outputs; ii. an instruction register coupled to the test data input, the test data output, and the control outputs, and having instruction outputs; iii. a data register coupled to the test data input, the test data output, and the instruction outputs; and iv. multiplexer circuitry coupling the test data output to the instruction register and to the data register; C. input linking circuitry including multiplexing circuitry selectively coupling test data input signals to the first and second TAP circuitry and selectively coupling the test data output signal from the second TAP circuitry to the first TAP circuitry in response to linking control signal inputs, the input linking circuitry including gating circuitry selectively coupling test mode select signals to the first and second TAP circuitry in response to the linking control signal inputs; D. output linking circuitry including multiplexing circuitry selectively coupling the test data outputs of the first and second TAP circuitry to a test data output lead in response to the linking control signal inputs; and E. TAP linking module circuitry coupled in series with the test data inputs and outputs of the first and second TAP circuitry and having linking control signal outputs connected to the linking control signal inputs of the input linking circuitry and the output linking circuitry, the TAP linking module circuitry being free of any connection of control signals from the first and second TAP circuitry.

References Cited (Backward Citations)

US5606566A Cited
US6658614B1 Cited
US6587981B1 Cited
US7058862B2 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2011-06-17 2011-12-17 2012-06-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2015-06-17 2015-12-17 2016-06-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2019-06-17 2019-12-17 2020-06-17 $7700.00 Window Closed / Lapsed

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