SLUSAH4D MARCH   2011  – February 2016 TPS56121

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
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Voltage Reference
      2. 7.3.2  Enable Functionality, Startup Sequence and Timing
        1. 7.3.2.1 COMP Pin Impedance Sensing
        2. 7.3.2.2 Overcurrent Protection (OCP) Setting
      3. 7.3.3  Soft-Start Time
      4. 7.3.4  Oscillator
      5. 7.3.5  Overcurrent Protection (OCP)
      6. 7.3.6  Switching Node (SW)
      7. 7.3.7  Input Undervoltage Lockout (UVLO)
      8. 7.3.8  Pre-Bias Startup
      9. 7.3.9  Power Good
      10. 7.3.10 Thermal Shutdown
    4. 7.4 Device Functional Modes
  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  Switching Frequency Selection
        2. 8.2.2.2  Inductor Selection (L1)
        3. 8.2.2.3  Output Capacitor Selection
        4. 8.2.2.4  Inductor Peak Current Rating
        5. 8.2.2.5  Input Capacitor Selection
        6. 8.2.2.6  Bootstrap Capacitor (C14)
        7. 8.2.2.7  Bootstrap Resistor (R2)
        8. 8.2.2.8  RC Snubber (R9 and C18)
        9. 8.2.2.9  VDD Bypass Capacitor (C11)
        10. 8.2.2.10 BP5 Bypass Capacitor (C12)
        11. 8.2.2.11 Soft-Start Capacitor (C13)
        12. 8.2.2.12 Current Limit (R1)
        13. 8.2.2.13 Feedback Divider (R4, R7)
        14. 8.2.2.14 Compensation (C15, C16, C17, R3, R6)
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
    2. 11.2 Trademarks
    3. 11.3 Electrostatic Discharge Caution
    4. 11.4 Glossary
  12. 12Mechanical, 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

9 Power Supply Recommendations

The TPS56121 devices are designed to operate from an input voltage supply between 4.5 V and 14 V. This supply must be well regulated. These devices are not designed for split-rail operation. The VIN and VDD terminals must be the same potential for accurate high-side short circuit protection. Proper bypassing of input supplies and internal regulators is also critical for noise performance, as is PCB layout and grounding scheme. See the recommendations in Layout Guidelines.