JAJSQJ3E november   1988  – june 2023 SN74HCT257

PRODUCTION DATA  

  1.   1
  2. 特長
  3. 概要
  4. Revision History
  5. Pin Configuration and Functions
  6.   6
  7. Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 Recommended Operating Conditions #GUID-E2584F18-4229-491B-88C0-5C0565546F3D/GUID-6412D0F1-0296-497F-B98D-0D6926824395
    3. 5.3 Thermal Information
    4. 5.4 Electrical Characteristics
    5. 5.5 Switching Characteristics
    6. 5.6 Switching Characteristics
    7. 5.7 Operating Characteristics
  8. Parameter Measurement Information
  9. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
  10. Device Functional Modes
  11. Power Supply Recommendations
  12. 10Layout
    1. 10.1 Layout Guidelines
  13. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 ドキュメントの更新通知を受け取る方法
    3. 11.3 サポート・リソース
    4. 11.4 Trademarks
    5. 11.5 静電気放電に関する注意事項
    6. 11.6 用語集
  14. 12Mechanical, Packaging, and Orderable Information
    1. 12.1 Tape and Reel Information
    2. 12.2 Mechanical Data

パッケージ・オプション

デバイスごとのパッケージ図は、PDF版データシートをご参照ください。

メカニカル・データ(パッケージ|ピン)
  • N|16
  • D|16
サーマルパッド・メカニカル・データ
発注情報

Layout Guidelines

When using multiple-input and multiple-channel logic devices inputs must not ever be left floating. In many cases, functions or parts of functions of digital logic devices are unused; for example, when only two inputs of a triple-input AND gate are used or only 3 of the 4 buffer gates are used. Such unused input pins must not be left unconnected because the undefined voltages at the outside connections result in undefined operational states. All unused inputs of digital logic devices must be connected to a logic high or logic low voltage, as defined by the input voltage specifications, to prevent them from floating. The logic level that must be applied to any particular unused input depends on the function of the device. Generally, the inputs are tied to GND or VCC, whichever makes more sense for the logic function or is more convenient.