ZHCSOD2E December   1982  – June 2021 SN54HC27 , SN74HC27

PRODUCTION DATA  

  1. 特性
  2. 应用
  3. 说明
  4. Revision History
  5. Pin Configuration and Functions
    1.     Pin Functions
  6. Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 Recommended Operating Conditions
    3. 6.3 Thermal Information
    4. 6.4 Electrical Characteristics - 74
    5. 6.5 Electrical Characteristics - 54
    6. 6.6 Switching Characteristics - 74
    7. 6.7 Switching Characteristics - 54
    8. 6.8 Operating Characteristics
    9. 6.9 Typical Characteristics
  7. Parameter Measurement Information
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Balanced CMOS Push-Pull Outputs
      2. 8.3.2 Standard CMOS Inputs
      3. 8.3.3 Clamp Diode Structure
    4. 8.4 Device Functional Modes
  9. Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
        1. 9.2.1.1 Power Considerations
        2. 9.2.1.2 Input Considerations
        3. 9.2.1.3 Output Considerations
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 支持资源
    3. 12.3 Trademarks
    4. 12.4 静电放电警告
    5. 12.5 术语表
  13. 13Mechanical, Packaging, and Orderable Information

封装选项

请参考 PDF 数据表获取器件具体的封装图。

机械数据 (封装 | 引脚)
  • D|14
  • DB|14
  • N|14
  • NS|14
散热焊盘机械数据 (封装 | 引脚)
订购信息

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 SN74HC27, as specified in the GUID-3ABB105B-A680-4E29-8298-466CC52D7528.html#GUID-3ABB105B-A680-4E29-8298-466CC52D7528, and the desired input transition rate. A 10-kΩ resistor value is often used due to these factors.

The SN74HC27 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 GUID-21AD65E0-3428-4493-BB6D-29EA624FF219.html#GUID-21AD65E0-3428-4493-BB6D-29EA624FF219.

Refer to the GUID-3570DEC6-93D1-424D-B6F7-497512E9CF03.html#GUID-3570DEC6-93D1-424D-B6F7-497512E9CF03 for additional information regarding the inputs for this device.