9-Bit D-Type Transparent Read-Back Latches With 3-State Outputs


Product details


Channels (#) 9 Technology Family ALS VCC (Min) (V) 4.5 VCC (Max) (V) 5.5 Input type Bipolar Output type 3-State Clock Frequency (Max) (MHz) 75 IOL (Max) (mA) 24 IOH (Max) (mA) -2.6 ICC (Max) (uA) 80000 Features High speed (tpd 10-50ns), Flow-through pinout open-in-new Find other D-type latch

Package | Pins | Size

SOIC (DW) 24 160 mm² 15.5 x 10.3 open-in-new Find other D-type latch


  • 3-State I/O-Type Read-Back Inputs
  • Bus-Structured Pinout
  • True Logic Outputs
  • Designed With Nine Bits for Parity Applications
  • Package Options Include Plastic Small-Outline (DW) Packages and Standard Plastic (NT) 300-mil DIPs


open-in-new Find other D-type latch


This 9-bit latch is designed specifically for storing the contents of the input data bus and providing the capability of reading back the stored data onto the input data bus. In addition, this device provides a 3-state buffer-type output and is easily implemented in parity applications.

The nine latches are transparent D-type latches. While the latch-enable (LE) input is high, the Q outputs follow the data (D) inputs. The Q outputs are in the 3-state condition when the output-enable () input is high.

Read back is provided through the output-enable () input. When is taken low, the data present at the output of the data latches is allowed to pass back onto the input data bus. When is taken high, the output of the data latches is isolated from the D inputs. does not affect the internal operation of the latches; however, precautions should be taken not to create a bus conflict.

The SN74ALS992 is characterized for operation from 0°C to 70°C.

open-in-new Find other D-type latch

Technical documentation

= Top documentation for this product selected by TI
No results found. Please clear your search and try again. View all 13
Type Title Date
* Datasheet 9-Bit D-Type Trans Read-Back Latch With 3-State Outputs datasheet (Rev. B) Jan. 01, 1995
Selection guides Logic Guide (Rev. AB) Jun. 12, 2017
Application notes Understanding and Interpreting Standard-Logic Data Sheets (Rev. C) Dec. 02, 2015
Application notes Power-Up Behavior of Clocked Devices (Rev. A) Feb. 06, 2015
User guides LOGIC Pocket Data Book (Rev. B) Jan. 16, 2007
Application notes Semiconductor Packing Material Electrostatic Discharge (ESD) Protection Jul. 08, 2004
More literature Logic Cross-Reference (Rev. A) Oct. 07, 2003
Application notes TI IBIS File Creation, Validation, and Distribution Processes Aug. 29, 2002
Application notes Bus-Interface Devices With Output-Damping Resistors Or Reduced-Drive Outputs (Rev. A) Aug. 01, 1997
Application notes Designing With Logic (Rev. C) Jun. 01, 1997
Application notes Input and Output Characteristics of Digital Integrated Circuits Oct. 01, 1996
Application notes Live Insertion Oct. 01, 1996
Application notes Advanced Schottky (ALS and AS) Logic Families Aug. 01, 1995

Design & development

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

Hardware development

document-generic User guide
This EVM is designed to support any logic device that has a D, DW, DB, NS, PW, P, N, or DGV package in a 14 to 24 pin count.
  • Board design allows for versatility in evaluation
  • Supports a wide-range of logic devices

CAD/CAE symbols

Package Pins Download
SOIC (DW) 24 View options

Ordering & quality

Support & training

TI E2E™ forums with technical support from TI engineers

Content is provided "as is" by TI and community contributors and does not constitute TI specifications. See terms of use.

If you have questions about quality, packaging or ordering TI products, see TI support. ​​​​​​​​​​​​​​


Related videos