SNVSA40A October   2014  – March 2016 TPS61169

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Simplified Schematic
  5. 5 Revision History
  6. 6 Pin Configuration and Functions
  7. 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
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Soft Start-Up
      2. 8.3.2 Open LED Protection
      3. 8.3.3 Shutdown
      4. 8.3.4 Current Program
      5. 8.3.5 LED Brightness Dimming
      6. 8.3.6 Undervoltage Lockout
      7. 8.3.7 Thermal Foldback and Thermal Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 Operation With CTRL
  9. 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 Inductor Selection
        2. 9.2.2.2 Schottky Diode Selection
        3. 9.2.2.3 Output Capacitor Selection
        4. 9.2.2.4 LED Current Set Resistor
        5. 9.2.2.5 Thermal Considerations
    3. 9.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Third-Party Products Disclaimer
    2. 12.2 Community Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, 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
発注情報

11 Layout

11.1 Layout Guidelines

As for all switching power supplies, especially those high frequency and high current ones, layout is an important design step. If layout is not carefully done, the regulator could suffer from instability as well as noise problems. Therefore, use wide and short traces for high current paths. The input capacitor CIN must be close to VIN pin and GND pin in order to reduce the input ripple seen by the device. If possible choose higher capacitance value for it. The SW pin carries high current with fast rising and falling edge; therefore, the connection between the SW pin to the inductor must be kept as short and wide as possible. The output capacitor COUT must be put close to VOUT pin. It is also beneficial to have the ground of COUT close to the GND pin because there is large ground return current flowing between them. FB resistor must be put close to FB pin. When laying out signal ground, TI recommends using short traces separated from power ground traces, and connect them together at a single point close to the GND pin.

11.2 Layout Example

TPS61169 layout_drawing_snvsa40.gif Figure 18. TPS61169 Board Layout