Product details

Technology family ABT Rating Military Operating temperature range (°C) -40 to 85
Technology family ABT Rating Military Operating temperature range (°C) -40 to 85
SOIC (DW) 24 159.65 mm² 15.5 x 10.3 TSSOP (PW) 24 49.92 mm² 7.8 x 6.4
  • Members of Texas Instruments Broad Family of Testability Products Supporting IEEE Std 1149.1-1990 (JTAG) Test Access Port (TAP) and Boundary-Scan Architecture
  • Extend Scan Access From Board Level to Higher Levels of System Integration
  • Promote Reuse of Lower-Level (Chip/Board) Tests in System Environment
  • Switch-Based Architecture Allows Direct Connect of Primary TAP to Secondary TAP
  • Primary TAP Is Multidrop for Minimal Use of Backplane Wiring Channels
  • Simple Addressing (Shadow) Protocol Is Received/Acknowledged on Primary TAP
  • Shadow Protocols Can Occur in Any of Test-Logic-Reset, Run-Test/Idle, Pause-DR, and Pause-IR TAP States to Provide for Board-to-Board Test and Built-In Self-Test
  • 10-Bit Address Space Provides for Up to 1021 User-Specified Board Addresses
  • Bypass (BYP\) Pin Forces Primary-to-Secondary Connection Without Use of Shadow Protocols
  • Connect (CON\) Pin Provides Indication of Primary-to-Secondary Connection
  • High-Drive Outputs (-32-mA IOH, 64-mA IOL) Support Backplane Interface at Primary and High Fanout at Secondary
  • Package Options Include Plastic Small- Outline (DW) and Thin Shrink Small- Outline (PW) Packages, Ceramic Chip Carriers (FK), and Ceramic DIPs (JT)

SCOPE is a trademark of Texas Instruments Incorporated.

  • Members of Texas Instruments Broad Family of Testability Products Supporting IEEE Std 1149.1-1990 (JTAG) Test Access Port (TAP) and Boundary-Scan Architecture
  • Extend Scan Access From Board Level to Higher Levels of System Integration
  • Promote Reuse of Lower-Level (Chip/Board) Tests in System Environment
  • Switch-Based Architecture Allows Direct Connect of Primary TAP to Secondary TAP
  • Primary TAP Is Multidrop for Minimal Use of Backplane Wiring Channels
  • Simple Addressing (Shadow) Protocol Is Received/Acknowledged on Primary TAP
  • Shadow Protocols Can Occur in Any of Test-Logic-Reset, Run-Test/Idle, Pause-DR, and Pause-IR TAP States to Provide for Board-to-Board Test and Built-In Self-Test
  • 10-Bit Address Space Provides for Up to 1021 User-Specified Board Addresses
  • Bypass (BYP\) Pin Forces Primary-to-Secondary Connection Without Use of Shadow Protocols
  • Connect (CON\) Pin Provides Indication of Primary-to-Secondary Connection
  • High-Drive Outputs (-32-mA IOH, 64-mA IOL) Support Backplane Interface at Primary and High Fanout at Secondary
  • Package Options Include Plastic Small- Outline (DW) and Thin Shrink Small- Outline (PW) Packages, Ceramic Chip Carriers (FK), and Ceramic DIPs (JT)

SCOPE is a trademark of Texas Instruments Incorporated.

The 'ABT8996 10-bit addressable scan ports (ASP) are members of the Texas Instruments (TITM) SCOPETM testability integrated-circuit family. This family of devices supports IEEE Standard 1149.1-1990 boundary scan to facilitate testing of complex circuit assemblies. Unlike most SCOPETM devices, the ASP is not a boundary-scannable device, rather, it applies TI's addressable-shadow-port technology to the IEEE Standard 1149.1-1990 (JTAG) test access port (TAP) to extend scan access beyond the board level.

Conceptually, the ASP is a simple switch that can be used to directly connect a set of multidrop primary TAP signals to a set of secondary TAP signals - for example, to interface backplane TAP signals to a board-level TAP. The ASP provides all signal buffering that might be required at these two interfaces. When primary and secondary TAPs are connected, only a moderate propagation delay is introduced - no storage/retiming elements are inserted. This minimizes the need for reformatting board-level test vectors for in-system use.

Most operations of the ASP are synchronous to the primary test clock (PTCK) input. This PTCK signal always is buffered directly onto the secondary test clock (STCK) output.

Upon power up of the device, the ASP assumes a condition in which the primary TAP is disconnected from the secondary TAP (unless the bypass signal is used, as below). This reset condition also can be entered by the assertion of the primary test reset (PTRST\) input or by use of shadow protocol. The PTRST\ signal is always buffered directly onto the secondary test reset (STRST\) output, ensuring that the ASP and its associated secondary TAP can be reset simultaneously.

When connected, the primary test data input (PTDI) and primary test mode select (PTMS) input are buffered onto the secondary test data output (STDO) and secondary test mode select (STMS) output, respectively, while the secondary test data input (STDI) is buffered onto the primary test data output (PTDO). When disconnected, STDO is at high impedance, while PTDO is at high impedance, except during acknowledgement of a shadow protocol. Upon disconnect of the secondary TAP, STMS holds its last low or high level, allowing the secondary TAP to be held in its last stable state. Upon reset of the ASP, STMS is high, allowing the secondary TAP to be synchronously reset to the Test-Logic-Reset state.

In system, primary-to-secondary connection is based on shadow protocols that are received and acknowledged on PTDI and PTDO, respectively. These protocols can occur in any of the stable TAP states other than Shift-DR or Shift-IR (i.e., Test-Logic-Reset, Run-Test/Idle, Pause-DR or Pause-IR). The essential nature of the protocols is to receive/transmit an address via a serial bit-pair signaling scheme. When an address is received serially at PTDI that matches that at the parallel address inputs (A9-A0), the ASP serially retransmits its address at PTDO as an acknowledgement and then assumes the connected (ON) status, as above. If the received address does not match that at the address inputs, the ASP immediately assumes the disconnected (OFF) status without acknowledgement.

The ASP also supports three dedicated addresses that can be received globally (that is, to which all ASPs respond) during shadow protocols. Receipt of the dedicated disconnect address (DSA) causes the ASP to disconnect in the same fashion as a non-matching address. Reservation of this address for global use ensures that at least one address is available to disconnect all receiving ASPs. The DSA is especially useful when the secondary TAPs of multiple ASPs are to be left in different stable states. Receipt of the reset address (RSA) causes the ASP to assume the reset condition, as above. Receipt of the test-synchronization address (TSA) causes the ASP to assume a connect status (MULTICAST) in which PTDO is at high impedance but the connections from PTMS to STMS and PTDI to STDO are maintained to allow simultaneous operation of the secondary TAPs of multiple ASPs. This is useful for multicast TAP-state movement, simultaneous test operation (such as in Run-Test/Idle state), and scanning of common test data into multiple like scan chains. The TSA is valid only when received in the Pause-DR or Pause-IR TAP states.

Alternatively, primary-to-secondary connection can be selected by assertion of a low level at the bypass (BYP\) input. This operation is asynchronous to PTCK and is independent of PTRST\ and/or power-up reset. This bypassing feature is especially useful in the board-test environment, since it allows the board-level automated test equipment (ATE) to treat the ASP as a simple transceiver. When the BYP\ input is high, the ASP is free to respond to shadow protocols. Otherwise, when BYP\ is low, shadow protocols are ignored.

Whether the connected status is achieved by use of shadow protocol or by use of BYP\, this status is indicated by a low level at the connect (CON\) output. Likewise, when the secondary TAP is disconnected from the primary TAP, the CON\ output is high.

The SN54ABT8996 is characterized for operation over the full military temperature range of -55°C to 125°C. The SN74ABT8996 is characterized for operation from -40°C to 85°C.

The 'ABT8996 10-bit addressable scan ports (ASP) are members of the Texas Instruments (TITM) SCOPETM testability integrated-circuit family. This family of devices supports IEEE Standard 1149.1-1990 boundary scan to facilitate testing of complex circuit assemblies. Unlike most SCOPETM devices, the ASP is not a boundary-scannable device, rather, it applies TI's addressable-shadow-port technology to the IEEE Standard 1149.1-1990 (JTAG) test access port (TAP) to extend scan access beyond the board level.

Conceptually, the ASP is a simple switch that can be used to directly connect a set of multidrop primary TAP signals to a set of secondary TAP signals - for example, to interface backplane TAP signals to a board-level TAP. The ASP provides all signal buffering that might be required at these two interfaces. When primary and secondary TAPs are connected, only a moderate propagation delay is introduced - no storage/retiming elements are inserted. This minimizes the need for reformatting board-level test vectors for in-system use.

Most operations of the ASP are synchronous to the primary test clock (PTCK) input. This PTCK signal always is buffered directly onto the secondary test clock (STCK) output.

Upon power up of the device, the ASP assumes a condition in which the primary TAP is disconnected from the secondary TAP (unless the bypass signal is used, as below). This reset condition also can be entered by the assertion of the primary test reset (PTRST\) input or by use of shadow protocol. The PTRST\ signal is always buffered directly onto the secondary test reset (STRST\) output, ensuring that the ASP and its associated secondary TAP can be reset simultaneously.

When connected, the primary test data input (PTDI) and primary test mode select (PTMS) input are buffered onto the secondary test data output (STDO) and secondary test mode select (STMS) output, respectively, while the secondary test data input (STDI) is buffered onto the primary test data output (PTDO). When disconnected, STDO is at high impedance, while PTDO is at high impedance, except during acknowledgement of a shadow protocol. Upon disconnect of the secondary TAP, STMS holds its last low or high level, allowing the secondary TAP to be held in its last stable state. Upon reset of the ASP, STMS is high, allowing the secondary TAP to be synchronously reset to the Test-Logic-Reset state.

In system, primary-to-secondary connection is based on shadow protocols that are received and acknowledged on PTDI and PTDO, respectively. These protocols can occur in any of the stable TAP states other than Shift-DR or Shift-IR (i.e., Test-Logic-Reset, Run-Test/Idle, Pause-DR or Pause-IR). The essential nature of the protocols is to receive/transmit an address via a serial bit-pair signaling scheme. When an address is received serially at PTDI that matches that at the parallel address inputs (A9-A0), the ASP serially retransmits its address at PTDO as an acknowledgement and then assumes the connected (ON) status, as above. If the received address does not match that at the address inputs, the ASP immediately assumes the disconnected (OFF) status without acknowledgement.

The ASP also supports three dedicated addresses that can be received globally (that is, to which all ASPs respond) during shadow protocols. Receipt of the dedicated disconnect address (DSA) causes the ASP to disconnect in the same fashion as a non-matching address. Reservation of this address for global use ensures that at least one address is available to disconnect all receiving ASPs. The DSA is especially useful when the secondary TAPs of multiple ASPs are to be left in different stable states. Receipt of the reset address (RSA) causes the ASP to assume the reset condition, as above. Receipt of the test-synchronization address (TSA) causes the ASP to assume a connect status (MULTICAST) in which PTDO is at high impedance but the connections from PTMS to STMS and PTDI to STDO are maintained to allow simultaneous operation of the secondary TAPs of multiple ASPs. This is useful for multicast TAP-state movement, simultaneous test operation (such as in Run-Test/Idle state), and scanning of common test data into multiple like scan chains. The TSA is valid only when received in the Pause-DR or Pause-IR TAP states.

Alternatively, primary-to-secondary connection can be selected by assertion of a low level at the bypass (BYP\) input. This operation is asynchronous to PTCK and is independent of PTRST\ and/or power-up reset. This bypassing feature is especially useful in the board-test environment, since it allows the board-level automated test equipment (ATE) to treat the ASP as a simple transceiver. When the BYP\ input is high, the ASP is free to respond to shadow protocols. Otherwise, when BYP\ is low, shadow protocols are ignored.

Whether the connected status is achieved by use of shadow protocol or by use of BYP\, this status is indicated by a low level at the connect (CON\) output. Likewise, when the secondary TAP is disconnected from the primary TAP, the CON\ output is high.

The SN54ABT8996 is characterized for operation over the full military temperature range of -55°C to 125°C. The SN74ABT8996 is characterized for operation from -40°C to 85°C.

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Technical documentation

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Type Title Date
* Data sheet 10-Bit Addressable Scan Ports Multi-Drop Addressable IEEE 1149.1 datasheet (Rev. C) 15 Apr 1999
Application note Implications of Slow or Floating CMOS Inputs (Rev. E) 26 Jul 2021
Selection guide Logic Guide (Rev. AB) 12 Jun 2017
Application note Understanding and Interpreting Standard-Logic Data Sheets (Rev. C) 02 Dec 2015
User guide LOGIC Pocket Data Book (Rev. B) 16 Jan 2007
EVM User's guide LASP Demo Board User's Guide 01 Nov 2005
Application note Programming CPLDs Via the 'LVT8986 LASP 01 Nov 2005
Application note Semiconductor Packing Material Electrostatic Discharge (ESD) Protection 08 Jul 2004
Application note Selecting the Right Level Translation Solution (Rev. A) 22 Jun 2004
Application note Quad Flatpack No-Lead Logic Packages (Rev. D) 16 Feb 2004
Application note TI IBIS File Creation, Validation, and Distribution Processes 29 Aug 2002
Application note Power-Up 3-State (PU3S) Circuits in TI Standard Logic Devices 10 May 2002
Selection guide Advanced Bus Interface Logic Selection Guide 09 Jan 2001
Application note Bus-Interface Devices With Output-Damping Resistors Or Reduced-Drive Outputs (Rev. A) 01 Aug 1997
Application note Advanced BiCMOS Technology (ABT) Logic Characterization Information (Rev. B) 01 Jun 1997
Application note Designing With Logic (Rev. C) 01 Jun 1997
Application note Advanced BiCMOS Technology (ABT) Logic Enables Optimal System Design (Rev. A) 01 Mar 1997
Application note Family of Curves Demonstrating Output Skews for Advanced BiCMOS Devices (Rev. A) 01 Dec 1996
Application note Input and Output Characteristics of Digital Integrated Circuits 01 Oct 1996
Application note Live Insertion 01 Oct 1996
Application note Understanding Advanced Bus-Interface Products Design Guide 01 May 1996

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SOIC (DW) 24 View options
TSSOP (PW) 24 View options

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