SLVSCN5B june   2014  – may 2023 TPS65262-1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Device Comparison Table
  7. 6 Pin Configuration and Functions
  8. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Typical Characteristics
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Adjusting the Output Voltage
      2. 8.3.2  Enable and Adjusting UVLO
      3. 8.3.3  Soft-Start Time
      4. 8.3.4  Power-Up Sequencing
        1. 8.3.4.1 External Power Sequencing
        2. 8.3.4.2 Automatic Power Sequencing
      5. 8.3.5  V7V Low Dropout Regulator and Bootstrap
      6. 8.3.6  Out-of-Phase Operation
      7. 8.3.7  Output Overvoltage Protection (OVP)
      8. 8.3.8  PSM
      9. 8.3.9  Slope Compensation
      10. 8.3.10 Overcurrent Protection (OCP)
        1. 8.3.10.1 High-Side MOSFET OCP
        2. 8.3.10.2 Low-Side MOSFET OCP
      11. 8.3.11 Power Good
      12. 8.3.12 Thermal Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 Operation With VIN < 4.5 V (Minimum VIN)
      2. 8.4.2 Operation With EN Control
      3. 8.4.3 Operation at Light Loads
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Output Inductor Selection
        2. 9.2.2.2 Output Capacitor Selection
        3. 9.2.2.3 Input Capacitor Selection
        4. 9.2.2.4 Loop Compensation
      3. 9.2.3 Application Curves
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Receiving Notification of Documentation Updates
    2. 10.2 Support Resources
    3. 10.3 Trademarks
    4. 10.4 Electrostatic Discharge Caution
    5. 10.5 Glossary
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

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

9.2.2.4 Loop Compensation

The TPS65262-1 incorporates a peak current mode control scheme. The error amplifier is a transconductance amplifier with a gain of 300 µS. A typical type II compensation circuit adequately delivers a phase margin between 60° and 90°. Cb adds a high frequency pole to attenuate high-frequency noise when needed. To calculate the external compensation components, follow these steps.

  1. Switching frequency, ƒsw, 600 kHz is appropriate for application depending on L and C sizes, output ripple, EMI, and so forth. It also gives the best trade-off between performance and cost.
  2. Set up crossover frequency, ƒc, which is typically between 1/5 and 1/20 of ƒsw.
  3. RC can be determined by Equation 16.
    Equation 16. GUID-5953CEA3-EDC2-4BFA-B828-3D7A09F3C231-low.gif

    where

    • Gm_EA is the error amplifier gain (300 µS)
    • Gm_PS is the power stage voltage to current conversion gain (7.4 A/V)
  4. Calculate CC by placing a compensation zero at or before the dominant pole GUID-CBEDA1E6-E8B6-4C6B-8ADA-9B5E2CDF0639-low.gif
    Equation 17. GUID-FAE24101-A242-489B-BE00-83A12353175A-low.gif
  5. Optional Cb can be used to cancel the zero from the ESR associated with CO.
    Equation 18. GUID-76A9ECD3-CE46-48F7-9E23-7FD79EF0CA38-low.gif
GUID-5C7D3FE7-1A4B-4E38-9F16-9CE527C5221E-low.svgFigure 9-1 DC/DC Loop Compensation