SCLS256O December   1995  – February 2024 SN54AHC125 , SN74AHC125

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, VCC = 3.3 V ± 0.3 V
    7. 5.7  Switching Characteristics, VCC = 5 V ± 0.5 V
    8. 5.8  Noise Characteristics
    9. 5.9  Operating Characteristics
    10. 5.10 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
    4. 7.4 Device Functional Modes
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
        1. 8.4.1.1 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Documentation Support (Analog)
      1. 9.1.1 Related Documentation
      2. 9.1.2 Related Links
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • J|14
  • FK|20
  • W|14
Thermal pad, mechanical data (Package|Pins)
Orderable Information

8.2.1 Design Requirements

It is best to set VCC for the SN74AHC125 to the same level as the microcontroller logic levels. This allows for optimal performance. The SN74AHC125 can safely handle input levels from –0.5 V to 7 V. However, if the logic levels that are being received vary from the VCC level of the device then errors can occur. For example, if VCC is 5.5 V then the minimum high-level input voltage (VIH) level is 3.85 V. This means if the microcontroller is sending a HIGH signal, but HIGH = 3.3 V, it would be too low a level for the SNx4AHC125 to register it as what it must be. In this case VCC would need to be lowered in order to lower the VIH minimum. The opposite is also true for low-level input voltage (VIL). If VCC is set to 2 V, then VIL maximum is 0.5 V. Depending on the microcontroller logic levels, a LOW signal may not go low enough for the SNx4AHC125 to register it.