Product details

Supply voltage (min) (V) 4.5 Supply voltage (max) (V) 5.5 Number of channels 8 IOL (max) (mA) 64 IOH (max) (mA) -32 Input type TTL Output type TTL Features Over-voltage tolerant inputs, Partial power down (Ioff), Very high speed (tpd 5-10ns) Technology family ABT Rating Catalog Operating temperature range (°C) -40 to 85
Supply voltage (min) (V) 4.5 Supply voltage (max) (V) 5.5 Number of channels 8 IOL (max) (mA) 64 IOH (max) (mA) -32 Input type TTL Output type TTL Features Over-voltage tolerant inputs, Partial power down (Ioff), Very high speed (tpd 5-10ns) Technology family ABT Rating Catalog Operating temperature range (°C) -40 to 85
SOIC (DW) 24 159.65 mm² 15.5 x 10.3 SOP (NS) 24 117 mm² 15 x 7.8 SSOP (DB) 24 63.96 mm² 8.2 x 7.8 TSSOP (PW) 24 49.92 mm² 7.8 x 6.4
  • Typical VOLP (Output Ground Bounce)
    <1 V at VCC = 5 V, TA = 25°C
  • High-Drive Outputs (-32-mA IOH, 64-mA IOL)
  • Ioff Supports Partial-Power-Down Mode Operation
  • Latch-Up Performance Exceeds 500 mA Per JEDEC Standard JESD-17
  • ESD Protection Exceeds JESD 22
    • 2000-V Human-Body Model (A114-A)
    • 200-V Machine Model (A115-A)
  • Typical VOLP (Output Ground Bounce)
    <1 V at VCC = 5 V, TA = 25°C
  • High-Drive Outputs (-32-mA IOH, 64-mA IOL)
  • Ioff Supports Partial-Power-Down Mode Operation
  • Latch-Up Performance Exceeds 500 mA Per JEDEC Standard JESD-17
  • ESD Protection Exceeds JESD 22
    • 2000-V Human-Body Model (A114-A)
    • 200-V Machine Model (A115-A)

These devices consist of bus-transceiver circuits, D-type flip-flops, and control circuitry arranged for multiplexed transmission of data directly from the input bus or from the internal registers. Data on the A or B bus is clocked into the registers on the low-to-high transition of the appropriate clock (CLKAB or CLKBA) input. Figure 1 illustrates the four fundamental bus-management functions that can be performed with the ’ABT646A devices.

Output-enable (OE\) and direction-control (DIR) inputs are provided to control the transceiver functions. In the transceiver mode, data present at the high-impedance port can be stored in either register or in both.

The select-control (SAB and SBA) inputs can multiplex stored and real-time (transparent mode) data. The direction control (DIR) determines which bus receives data when OE\ is low. In the isolation mode (OE\ high), A data can be stored in one register and/or B data can be stored in the other register.

When an output function is disabled, the input function still is enabled and can be used to store and transmit data. Only one of the two buses, A or B, can be driven at a time.

These devices are fully specified for partial-power-down applications using Ioff. The Ioff circuitry disables the outputs, preventing damaging current backflow through the devices when they are powered down.

To ensure the high-impedance state during power up or power down, OE\ should be tied to VCC through a pullup resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver.

These devices consist of bus-transceiver circuits, D-type flip-flops, and control circuitry arranged for multiplexed transmission of data directly from the input bus or from the internal registers. Data on the A or B bus is clocked into the registers on the low-to-high transition of the appropriate clock (CLKAB or CLKBA) input. Figure 1 illustrates the four fundamental bus-management functions that can be performed with the ’ABT646A devices.

Output-enable (OE\) and direction-control (DIR) inputs are provided to control the transceiver functions. In the transceiver mode, data present at the high-impedance port can be stored in either register or in both.

The select-control (SAB and SBA) inputs can multiplex stored and real-time (transparent mode) data. The direction control (DIR) determines which bus receives data when OE\ is low. In the isolation mode (OE\ high), A data can be stored in one register and/or B data can be stored in the other register.

When an output function is disabled, the input function still is enabled and can be used to store and transmit data. Only one of the two buses, A or B, can be driven at a time.

These devices are fully specified for partial-power-down applications using Ioff. The Ioff circuitry disables the outputs, preventing damaging current backflow through the devices when they are powered down.

To ensure the high-impedance state during power up or power down, OE\ should be tied to VCC through a pullup resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver.

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Technical documentation

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Type Title Date
* Data sheet SN54ABT646A, SN74ABT646A datasheet (Rev. H) 03 May 2004
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
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

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Evaluation board

14-24-LOGIC-EVM — Logic product generic evaluation module for 14-pin to 24-pin D, DB, DGV, DW, DYY, NS and PW packages

The 14-24-LOGIC-EVM evaluation module (EVM) is designed to support any logic device that is in a 14-pin to 24-pin D, DW, DB, NS, PW, DYY or DGV package,

User guide: PDF | HTML
Not available on TI.com
Package Pins CAD symbols, footprints & 3D models
SOIC (DW) 24 Ultra Librarian
SOP (NS) 24 Ultra Librarian
SSOP (DB) 24 Ultra Librarian
TSSOP (PW) 24 Ultra Librarian

Ordering & quality

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Information included:
  • Fab location
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