SNVSC83B September   2022  – February 2023 TPSM365R3 , TPSM365R6

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Description (continued)
  6. Device Comparison Table
  7. Pin Configuration and Functions
  8. Specifications
    1. 8.1  Absolute Maximum Ratings
    2. 8.2  ESD Ratings
    3. 8.3  Recommended Operating Conditions
    4. 8.4  Thermal Information
    5. 8.5  Electrical Characteristics
    6. 8.6  System Characteristics
    7. 8.7  Typical Characteristics
    8. 8.8  Typical Characteristics: VIN = 12 V
    9. 8.9  Typical Characteristics: VIN = 24 V
    10. 8.10 Typical Characteristics: VIN = 48 V
  9. Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1  Input Voltage Range
      2. 9.3.2  Output Voltage Selection
      3. 9.3.3  Input Capacitors
      4. 9.3.4  Output Capacitors
      5. 9.3.5  Enable, Start-Up, and Shutdown
      6. 9.3.6  External CLK SYNC (with MODE/SYNC)
        1. 9.3.6.1 Pulse-Dependent MODE/SYNC Pin Control
      7. 9.3.7  Switching Frequency (RT)
      8. 9.3.8  Power-Good Output Operation
      9. 9.3.9  Internal LDO, VCC UVLO, and BIAS Input
      10. 9.3.10 Bootstrap Voltage and VBOOT-UVLO (BOOT Terminal)
      11. 9.3.11 Spread Spectrum
      12. 9.3.12 Soft Start and Recovery from Dropout
        1. 9.3.12.1 Recovery from Dropout
      13. 9.3.13 Overcurrent Protection (OCP)
      14. 9.3.14 Thermal Shutdown
    4. 9.4 Device Functional Modes
      1. 9.4.1 Shutdown Mode
      2. 9.4.2 Standby Mode
      3. 9.4.3 Active Mode
        1. 9.4.3.1 CCM Mode
        2. 9.4.3.2 AUTO Mode - Light Load Operation
          1. 9.4.3.2.1 Diode Emulation
          2. 9.4.3.2.2 Frequency Reduction
        3. 9.4.3.3 FPWM Mode - Light Load Operation
        4. 9.4.3.4 Minimum On-time (High Input Voltage) Operation
      4. 9.4.4 Dropout
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 600-mA and 300-mA Synchronous Buck Regulator for Industrial Applications
        1. 10.2.1.1 Design Requirements
        2. 10.2.1.2 Detailed Design Procedure
          1. 10.2.1.2.1  Custom Design With WEBENCH® Tools
          2. 10.2.1.2.2  Output Voltage Setpoint
          3. 10.2.1.2.3  Switching Frequency Selection
          4. 10.2.1.2.4  Input Capacitor Selection
          5. 10.2.1.2.5  Output Capacitor Selection
          6. 10.2.1.2.6  VCC
          7. 10.2.1.2.7  CFF Selection
          8. 10.2.1.2.8  Power-Good Signal
          9. 10.2.1.2.9  Maximum Ambient Temperature
          10. 10.2.1.2.10 Other Connections
        3. 10.2.1.3 Application Curves
    3. 10.3 Power Supply Recommendations
    4. 10.4 Layout
      1. 10.4.1 Layout Guidelines
        1. 10.4.1.1 Ground and Thermal Considerations
      2. 10.4.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
      2. 11.1.2 Device Nomenclature
      3. 11.1.3 Development Support
        1. 11.1.3.1 Custom Design With WEBENCH® Tools
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Support Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information
Maximum Ambient Temperature

As with any power conversion module, the TPSM365Rx 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 TPSM365Rx must be limited to 125°C. This establishes a limit on the maximum module power dissipation and, therefore, the load current. Equation 12 shows the relationships between the important parameters. It is easy to see that larger ambient temperatures (TA) and larger values of RθJA reduce the maximum available output current. The power module efficiency can be estimated by using the curves provided in this data sheet. If the desired operating conditions cannot be found in one of the curves, interpolation can be used to estimate the efficiency. Alternatively, the EVM can be adjusted to match the desired application requirements and the efficiency can be measured directly. The correct value of RθJA is more difficult to estimate. As stated in the Semiconductor and IC Package Thermal Metrics application report the values given in Thermal Information 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 12. IOUT|MAX=(TJ-TA)RθJA×η1-η×1VOUT

where

  • η is the efficiency.

The effective RθJA is a critical parameter and depends on many factors such as the following:

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

As a reference, the effective RθJA on the EVM for typical 24-V VIN 5-V VOUT full-load condition is around 30 °C/W. Use the following resources as guides to optimal thermal PCB design and estimating RθJA for a given application environment: