JAJSO66A December   2023  – January 2024 TPS61289

PRODUCTION DATA  

  1.   1
  2. 1 特長
  3. 2 アプリケーション
  4. 3 概要
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Bidirectional Operation Configuration
      2. 6.3.2 VCC Power Supply
      3. 6.3.3 VHIGH and VCC Undervoltage Lockout (UVLO)
      4. 6.3.4 Enable and Programmable EN/UVLO
      5. 6.3.5 Switching Frequency
      6. 6.3.6 Programmable Switching Peak and Valley Current Limit
      7. 6.3.7 External Clock Synchronization
      8. 6.3.8 VHIGH Overvoltage Protection
      9. 6.3.9 Thermal Shutdown
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
        1. 7.2.2.1 Bootstrap Capacitor Selection
        2. 7.2.2.2 Inductor Selection
        3. 7.2.2.3 MOSFET Selection
        4. 7.2.2.4 VLOW/VHIGH Output Capacitor Selection
      3. 7.2.3 Application Curves
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
        1. 7.4.2.1 Thermal Considerations
  9. 8 Device and Documentation Support
    1. 8.1 Documentation Support
      1. 8.1.1 Related Documentation
    2. 8.2 Receiving Notification of Documentation Updates
    3. 8.3 サポート・リソース
    4. 8.4 Trademarks
    5. 8.5 静電気放電に関する注意事項
    6. 8.6 用語集
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

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

7.4.2.1 Thermal Considerations

The maximum IC junction temperature must be restricted to 125°C under normal operating conditions. Calculate the maximum allowable dissipation, PD(max), and keep the actual power dissipation less than or equal to PD(max). The maximum-power-dissipation limit is determined using Equation 10.

Equation 10. P D ( m a x ) = 125 - T A R θ J A

where

  • TA is the maximum ambient temperature for the application.
  • RθJA is the junction-to-ambient thermal resistance given in the Thermal Information table.

The TPS61289 is in a thermally-enhanced VQFN package. The real junction-to-ambient thermal resistance of the package greatly depends on the PCB type, layout, and thermal pad connection. Using thick PCB copper and soldering the thermal pad to a large ground plate enhance the thermal performance. Increasing the number of vias that connect the ground plate on both the top and bottom layers around the IC, without solder mask, can also enhance the thermal capability.