SCAS531E August   1995  – February 2025 SN54ACT11 , SN74ACT11

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Description
  4. 3 Pin Configuration and Functions
  5. 4 Specifications
    1. 4.1 Absolute Maximum Ratings
    2. 4.2 Recommended Operating Conditions
    3. 4.3 Thermal Information
    4. 4.4 Electrical Characteristics
    5. 4.5 Switching Characteristics
    6. 4.6 Operating Characteristics
  6. 5 Parameter Measurement Information
  7. 6 Detailed Description
    1. 6.1 Functional Block Diagram
    2. 6.2 Device Functional Modes
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
        1. 7.2.1.1 Power Considerations
        2. 7.2.1.2 Input Considerations
        3. 7.2.1.3 Output Considerations
      2. 7.2.2 Detailed Design Procedure
      3. 7.2.3 Application Curves
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
  9. 8 Device and Documentation Support
    1. 8.1 Documentation Support (Analog)
      1. 8.1.1 Related Links
    2. 8.2 Receiving Notification of Documentation Updates
    3. 8.3 Support Resources
    4. 8.4 Trademarks
    5. 8.5 Electrostatic Discharge Caution
    6. 8.6 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

7.2.1.2 Input Considerations

Unused inputs must be terminated to either VCC or ground. These can be directly terminated if the input is completely unused, or they can be connected with a pull-up or pull-down resistor if the input is to be used sometimes, but not always. A pull-up resistor is used for a default state of HIGH, and a pull-down resistor is used for a default state of LOW. The resistor size is limited by drive current of the controller, leakage current into the SN74HC11, as specified in the Electrical Characteristics, and the desired input transition rate. A 10-kΩ resistor value is often used due to these factors.

The SN74HC11 has standard CMOS inputs, so input signal edge rates cannot be slow. Slow input edge rates can cause oscillations and damaging shoot-through current. The recommended rates are defined in the Recommended Operating Conditions.

Refer to Feature Description for additional information regarding the inputs for this device.