JAJSH48 March   2019 SN74AXCH4T245

PRODUCTION DATA.  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
    1.     機能ブロック図
  4. 4 改訂履歴
  5. 5 概要（続き）
  6. 6 Pin Configuration and Functions
    1.     Pin Functions
  7. 7 Specifications
    1. 7.1  Absolute Maximum Ratings
    2. 7.2  ESD Ratings
    3. 7.3  Recommended Operating Conditions
    4. 7.4  Thermal Information
    5. 7.5  Electrical Characteristics
    6. 7.6  Switching Characteristics, VCCA = 0.7 ± 0.05 V
    7. 7.7  Switching Characteristics, VCCA = 0.8 ± 0.04 V
    8. 7.8  Switching Characteristics, VCCA = 0.9 ± 0.045 V
    9. 7.9  Switching Characteristics, VCCA = 1.2 ± 0.1 V
    10. 7.10 Switching Characteristics, VCCA = 1.5 ± 0.1 V
    11. 7.11 Switching Characteristics, VCCA = 1.8 ± 0.15 V
    12. 7.12 Switching Characteristics, VCCA = 2.5 ± 0.2 V
    13. 7.13 Switching Characteristics, VCCA = 3.3 ± 0.3 V
    14. 7.14 Operating Characteristics: TA = 25°C
    15. 7.15 Typical Characteristics
  8. 8 Parameter Measurement Information
    1. 8.1 Load Circuit and Voltage Waveforms
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1  Standard CMOS Inputs
      2. 9.3.2  Balanced High-Drive CMOS Push-Pull Outputs
      3. 9.3.3  Partial Power Down (Ioff)
      4. 9.3.4  VCC Isolation
      5. 9.3.5  Over-voltage Tolerant Inputs
      6. 9.3.6  Glitch-free Power Supply Sequencing
      7. 9.3.7  Negative Clamping Diodes
      8. 9.3.8  Fully Configurable Dual-Rail Design
      9. 9.3.9  Supports High-Speed Translation
      10. 9.3.10 Bus-Hold Data Inputs
    4. 9.4 Device Functional Modes
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
      3. 10.2.3 Application Curve
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13デバイスおよびドキュメントのサポート
    1. 13.1 関連資料
    2. 13.2 ドキュメントの更新通知を受け取る方法
    3. 13.3 コミュニティ・リソース
    4. 13.4 商標
    5. 13.5 静電気放電に関する注意事項
    6. 13.6 Glossary
  14. 14メカニカル、パッケージ、および注文情報

パッケージ・オプション

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

9.3.10 Bus-Hold Data Inputs

Each data input on this device includes a weak latch that maintains a valid logic level on the input. The state of these latches is unknown at startup and remains unknown until the input has been forced to a valid high or low state. After data has been sent through a channel, the latch then maintains the previous state on the input if the line is left floating. It is not recommended to use pull-up or pull-down resistors together with a bus-hold input, as it may cause undefined inputs to occur which leads to excessive current consumption.

Bus-hold data inputs prevent floating inputs on this device. The Implications of Slow or Floating CMOS Inputs application report explains the problems associated with leaving CMOS inputs floating.

These latches remain active at all times, independent of all control signals such as direction control or output enable.

The Bus-Hold Circuit application report has additional details regarding bus-hold inputs.

SN74AXCH4T245 Feature_Bus-Hold.gifFigure 10. Simplified Schematic For Device With Bus-Hold Data Inputs