SLVSBR3A May   2013  – June 2015

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 EasyScale Timing Requirements
    7. 6.7 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 Soft Start-Up
      2. 7.3.2 Shutdown
      3. 7.3.3 Current Program
      4. 7.3.4 Undervoltage Lockout
      5. 7.3.5 Open LED Protection
      6. 7.3.6 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 LED Brightness Dimming Mode Selection
        1. 7.4.1.1 PWM Brightness Dimming
          1. 7.4.1.1.1 Digital 1-Wire Brightness Dimming
          2. 7.4.1.1.2 Easyscale: 1-Wire Digital Dimming
  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 Inductor Selection
        2. 8.2.2.2 Maximum Output Current
        3. 8.2.2.3 Input and Output Capacitor Selection
      3. 8.2.3 Application Curves
      4. 8.2.4 Additional Application Circuits
        1. 8.2.4.1 TPS61158 To Drive Up To 8 LEDs
        2. 8.2.4.2 TPS61158 to Drive up to 8 LEDs with RC Filter at VIN Pin
  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 Community Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

10 Layout

10.1 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 needs to be close to the VIN pin and GND pin in order to reduce the input ripple seen by the device. If possible, choose higher capacitance value for it. If the ripple seen at VIN pin is so large that it affects the boost loop stability or internal circuits operation, R1 and C1 is recommended to compose a filter to decouple the noise (refer to Figure 24). The SW pin carries high current with fast rising and falling edges. Therefore, the connection between the SW pin to the inductor should be kept as short and wide as possible. The output capacitor COUT should be put close to VOUT pin. It is also beneficial to have the ground of COUT close to the GND pin since there is large ground return current flowing between them. FB resistor should be put close to FB pin. When laying out signal grounds, it is recommended to use short traces separated from power ground traces, and connect them together at a single point close to the GND pin.

10.2 Layout Example

TPS61158 TPS61158_layout.gifFigure 25. TPS61158 Example Layout