SCLSA04 March   2024 SN74AHC138-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Switching Characteristics
    7. 5.7 Noise Characteristics
    8. 5.8 Typical Characteristics
  7. 6 Parameter Measurement Information
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Balanced CMOS Push-Pull Outputs
      2. 7.3.2 Standard CMOS Inputs
      3. 7.3.3 Wettable Flanks
      4. 7.3.4 Clamp Diode Structure
    4. 7.4 Device Functional Modes
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
    3. 8.3 Design Requirements
      1. 8.3.1 Power Considerations
      2. 8.3.2 Input Considerations
      3. 8.3.3 Output Considerations
    4. 8.4 Detailed Design Procedure
    5. 8.5 Application Curve
    6. 8.6 Power Supply Recommendations
    7. 8.7 Layout
      1. 8.7.1 Layout Guidelines
      2. 8.7.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Receiving Notification of Documentation Updates
    2. 9.2 Support Resources
    3. 9.3 Trademarks
    4. 9.4 Electrostatic Discharge Caution
    5. 9.5 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7.1 Overview

The SN74AHC138-Q1 is a 3-to-8 decoder/demultiplexer. The three input pins (A0, A1, and A2) select which output is active. The selected output is pulled LOW, while the remaining outputs are all HIGH. The conditions at the binary-select inputs at the three enable inputs select one of eight output lines. Two active-low and one active-high enable inputs reduce the requirement for external gates or inverters when expanding. A 24-line decoder can be implemented without external inverters, and a 32-line decoder requires only one inverter. A strobe input (G2, G1, or G0) can be used as a data input for demultiplexing applications.