SNVSC83B September   2022  – February 2023 TPSM365R3 , TPSM365R6

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Description (continued)
  6. 6 Device Comparison Table
  7. 7 Pin Configuration and Functions
  8. 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. 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

9.3.12 Soft Start and Recovery from Dropout

When designing with the TPSM365Rx, slow rise in output voltage due to recovery from dropout and soft start must be considered as a two separate operating conditions, as shown in #T5627962-27 and GUID-CFCDC1C7-E61E-45E0-B6BD-229661834025.html#T5627962-33. Soft start is triggered by any of the following conditions:

  • Power is applied to the VIN pin of the device, releasing undervoltage lockout.
  • EN is used to turn on the device.
  • Recovery from shutdown due to overtemperature protection.

After soft start is triggered, the power module takes the following actions:

  • The reference used by the power module to regulate the output voltage is slowly ramped up. The net result is that output voltage, if previously 0 V, takes tSS to reach 90% of the desired value.
  • Operating mode is set to auto mode of operation, activating the diode emulation mode for the low-side MOSFET. This allows start-up without pulling the output low. This is true even when there is a voltage already present at the output during a pre-bias start-up.
GUID-4AC0638A-1AB9-4872-AD80-4F8F9EA3EF89-low.gif Figure 9-11 Soft Start with and without Prebias Voltage