JAJSH18A March   2019  – September 2019 TPS7A78

PRODUCTION DATA.  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
    1.     Device Images
      1.      ハーフブリッジ構成の標準的な回路図
      2.      フルブリッジ構成の標準的な回路図
  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 Timing Requirements
    7. 7.7 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Active Bridge Control
      2. 8.3.2 Full-Bridge (FB) and Half-Bridge (HB) Configurations
      3. 8.3.3 4:1 Switched-Capacitor Voltage Reduction
      4. 8.3.4 Undervoltage Lockout Circuits (VUVLO_SCIN) and (VUVLO_LDO_IN)
      5. 8.3.5 Dropout Voltage Regulation
      6. 8.3.6 Current Limit
      7. 8.3.7 Programmable Power-Fail Detection
      8. 8.3.8 Power-Good (PG) Detection
      9. 8.3.9 Thermal Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 Normal Operation
      2. 8.4.2 Dropout Mode
      3. 8.4.3 Disabled Mode
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Recommended Capacitor Types
      2. 9.1.2 Input and Output Capacitors Requirements
      3. 9.1.3 Startup Behavior
      4. 9.1.4 Load Transient
      5. 9.1.5 Standby Power and Output Efficiency
      6. 9.1.6 Reverse Current
      7. 9.1.7 Switched-Capacitor Stage Output Impedance
      8. 9.1.8 Power Dissipation (PD)
      9. 9.1.9 Estimating Junction Temperature
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Calculating the Cap-Drop Capacitor CS
          1. 9.2.2.1.1 CS Calculations for the Typical Design
        2. 9.2.2.2 Calculating the Surge Resistor RS
          1. 9.2.2.2.1 RS Calculations for the Typical Design
        3. 9.2.2.3 Checking for the Device Maximum ISHUNT Current
          1. 9.2.2.3.1 ISHUNT Calculations for the Typical Design
        4. 9.2.2.4 Calculating the Bulk Capacitor CSCIN
          1. 9.2.2.4.1 CSCIN Calculations for the Typical Design
        5. 9.2.2.5 Calculating the PFD Pin Resistor Dividers for a Power-Fail Detection
          1. 9.2.2.5.1 PFD Pin Resistor Divider Calculations for the Typical Design
        6. 9.2.2.6 Summary of the Typical Application Design Components
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12デバイスおよびドキュメントのサポート
    1. 12.1 デバイス・サポート
      1. 12.1.1 開発サポート
        1. 12.1.1.1 評価基板
        2. 12.1.1.2 SIMPLIS モデル
      2. 12.1.2 デバイスの項目表記
    2. 12.2 ドキュメントのサポート
      1. 12.2.1 関連資料
    3. 12.3 ドキュメントの更新通知を受け取る方法
    4. 12.4 コミュニティ・リソース
    5. 12.5 商標
    6. 12.6 静電気放電に関する注意事項
    7. 12.7 Glossary
  13. 13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

8.3.8 Power-Good (PG) Detection

The power-good (PG) circuit monitors the VLDO_OUT voltage to indicate the status of the LDO output voltage. PG is pulled low until VLDO_OUT reaches its proper regulate voltage level, then PG is released and allowed to be pulled high. If VLDO_OUT falls below the VIT(PG_FALLING) threshold, PG is asserted low to indicate the LDO output voltage is not in regulation. PG pin low assertion can happen during an overcurrent event or a short-circuit fault.

PG can be used to release the reset pin of a microcontroller. The PG pin must be pulled up to a DC rail such as VLDO_OUT.

Use the recommended pullup resistor value specified in the Electrical Characteristics table for the PG pin. The functionality of the power-good detection pin has no effect on the internal control logic other than to indicate the state of the output voltage. If this function is not used, connect the PG pin to the device GND pins reference.

NOTE

An external DC rail can also be used to pull up the PG pin signal via a pullup resistor only when the external DC rail shares the same reference GND with the TPS7A78 GND and the absolute maximum voltage of the PG pin is not exceeded.