JAJSPL6A October   2023  – December 2023 TPSM365R1 , TPSM365R15

PRODUCTION DATA  

  1.   1
  2. 1 特長
  3. 2 アプリケーション
  4. 3 概要
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 System Characteristics
    7. 6.7 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Enable, Shutdown, and Start-Up
      2. 7.3.2  External CLK SYNC (With MODE/SYNC)
        1. 7.3.2.1 Pulse Dependent MODE/SYNC Pin Control
      3. 7.3.3  Adjustable Switching Frequency (with RT)
      4. 7.3.4  Power-Good Output Operation
      5. 7.3.5  Internal LDO, VCC UVLO, and VOUT/FB Input
      6. 7.3.6  Bootstrap Voltage and VBOOT-UVLO (BOOT Terminal)
      7. 7.3.7  Output Voltage Selection
      8. 7.3.8  Spread Spectrum
      9. 7.3.9  Soft Start and Recovery from Dropout
        1. 7.3.9.1 Soft Start
        2. 7.3.9.2 Recovery from Dropout
      10. 7.3.10 Current Limit and Short Circuit
      11. 7.3.11 Thermal Shutdown
      12. 7.3.12 Input Supply Current
    4. 7.4 Device Functional Modes
      1. 7.4.1 Shutdown Mode
      2. 7.4.2 Standby Mode
      3. 7.4.3 Active Mode
        1. 7.4.3.1 CCM Mode
        2. 7.4.3.2 AUTO Mode - Light Load Operation
          1. 7.4.3.2.1 Diode Emulation
          2. 7.4.3.2.2 Frequency Reduction
        3. 7.4.3.3 FPWM Mode - Light Load Operation
        4. 7.4.3.4 Minimum On-time Operation
        5. 7.4.3.5 Dropout
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1  Custom Design With WEBENCH® Tools
        2. 8.2.2.2  Choosing the Switching Frequency
        3. 8.2.2.3  Setting the Output Voltage
        4. 8.2.2.4  Input Capacitor Selection
        5. 8.2.2.5  Output Capacitor Selection
        6. 8.2.2.6  VCC
        7. 8.2.2.7  CFF Selection
        8. 8.2.2.8  External UVLO
        9. 8.2.2.9  Power-Good Signal
        10. 8.2.2.10 Maximum Ambient Temperature
        11. 8.2.2.11 Other Connections
      3. 8.2.3 Application Curves
    3. 8.3 Best Design Practices
    4. 8.4 Power Supply Recommendations
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
      2. 8.5.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Device Nomenclature
      2. 9.1.2 Development Support
        1. 9.1.2.1 Custom Design With WEBENCH® Tools
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 ドキュメントの更新通知を受け取る方法
    4. 9.4 サポート・リソース
    5. 9.5 Trademarks
    6. 9.6 静電気放電に関する注意事項
    7. 9.7 用語集
  11. 10Revision History
  12. 11Mechanical, 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

8.2.2.10 Maximum Ambient Temperature

As with any power conversion device, the TPSM365R15(F) dissipates internal power while operating. The effect of this power dissipation is to raise the internal temperature of the power module above ambient. The internal die and inductor temperature (TJ) is a function of the ambient temperature, the power loss, and the effective thermal resistance, RθJA, of the module and PCB combination. The maximum junction temperature for the TPSM365R15(F) must be limited to 125°C. This limit establishes a limit on the maximum module power dissipation and, therefore, the load current. Equation 9 shows the relationships between the important parameters. Seeing that larger ambient temperatures (TA) and larger values of RθJA reduce the maximum available output current is easy. Being that the power dissipation is relatively low in this module, this device must be capable of supporting the maximum ambient temperature rating, across the majority of power conditions with a modest size 2 layer or 4 layer PCB. Further thermal analysis can be done by measuring the top case temperature on the EVM which is nearly equivalent to the junction due to the thin case.

As stated in the Semiconductor and IC Package Thermal Metrics application report the values given in Section 6.4 section are not valid for design purposes and must not be used to estimate the thermal performance of the application. The values reported in that table were measured under a specific set of conditions that are rarely obtained in an actual application.

Equation 9. IOUT,max=(TJ-TA)RθJA×η(1-η)×1η

where

  • η is the efficiency.

The effective RθJA (TPSM365R15 approximately 56°C/W at 24 VIN, 5 VOUT, 150 mA, 1 MHz,) is a critical parameter and depends on many factors such as the following:

  • Power dissipation
  • Air temperature and flow
  • PCB area
  • Copper heat-sink area
  • Number of thermal vias under the package
  • Adjacent component placement

The IC Power loss mentioned above is the overall power loss minus the loss that comes from the inductor DC resistance. The overall power loss can be approximated by using WEBENCH for a specific operating condition and temperature.

Use the following resources as guides to optimal thermal PCB design and estimating RθJA for a given application environment: