SLVSEX5A October   2020  – December 2020 TPSM41615

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 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 Typical Characteristics (PVIN = 12 V)
    7. 6.7 Typical Characteristics (PVIN = 5 V)
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Setting the Output Voltage
      2. 7.3.2  RS+/RS- Remote Sense Function
      3. 7.3.3  Ramp Select (RAMP and RAMP_SEL)
      4. 7.3.4  Switching Frequency (RT)
      5. 7.3.5  Synchronization (SYNC)
        1. 7.3.5.1 Loss of Synchronization
      6. 7.3.6  Stand-alone/Stackable Operation
        1. 7.3.6.1 Stackable Synchronization
          1. 7.3.6.1.1 Sync Configuration
          2. 7.3.6.1.2 Clock Sync Point Selection
          3. 7.3.6.1.3 Configuration 1: Dual Phase, Primary Sync-Out Clock to Secondary
          4. 7.3.6.1.4 Configuration 2: Dual Phase, Primary and Secondary Sync to External System Clock
      7. 7.3.7  Improved Transient Performance versus Fixed Frequency (Stand-alone Operation Only)
      8. 7.3.8  Output On/Off Enable (EN)
      9. 7.3.9  Power Good (PGOOD)
      10. 7.3.10 Soft-Start Operation
      11. 7.3.11 Input Capacitor Selection
      12. 7.3.12 Output Capacitor Selection
      13. 7.3.13 Current Limit (ILIM)
      14. 7.3.14 Safe Start-up into Pre-Biased Outputs
      15. 7.3.15 Overcurrent Protection
      16. 7.3.16 Output Overvoltage and Undervoltage Protection
      17. 7.3.17 Overtemperature Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 Active Mode
      2. 7.4.2 Shutdown Mode
  8. 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 Output Voltage Setpoint
        3. 8.2.2.3 Setting the Switching Frequency
        4. 8.2.2.4 RAMP Setting
        5. 8.2.2.5 Input Capacitors
        6. 8.2.2.6 Output Capacitors
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Examples
      1. 10.2.1 Package Specifications
      2. 10.2.2 EMI
        1. 10.2.2.1 EMI Plots
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Development Support
        1. 11.1.1.1 Custom Design With WEBENCH® Tools
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7.3.7 Improved Transient Performance versus Fixed Frequency (Stand-alone Operation Only)

The TPSM41615 is a fixed frequency converter. The major limitation for any fixed frequency converter is that during transient load step up, the output voltage drops until the next clock cycle of the converter before it can respond to the load change. The TPSM41615 implements a special circuitry to improve transient performance. During a load step up, the converter can issue an additional PWM pulse before the next available clock cycle to stop output voltage from further dropping, thus reducing the undershoot voltage. The additional pulse during a transient means that the device is not fixed frequency during the transient.

During load step-down, the TPSM41615 implements a body-brake function that turns off both high-side and low-side FET, and allows power to dissipate through the low-side body diode, reducing overshoot. This approach is very effective while having some impact on efficiency during transient.

In stand-alone mode, choose whether the transient response feature is enabled by placing either a 78.7-kΩ or 187-kΩ resistor between the MODE pin and AGND. A 78.7-kΩ MODE resistor is recommended when the output voltage is 0.6 V to 1.8 V or in applications that are more susceptible to noise. Leave the MODE pin open to operate in fixed frequency during a load step, (see Table 7-8).

Table 7-8 Stand-Alone Operation Feature Selections
STAND-ALONE OPERATION MODE RESISTOR VALUE (kΩ)
Transient Feature 78.7
187
Fixed Frequency open