SLVSBK3A December   2012  – September 2015 TPS92690

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  Current Regulators
      2. 7.3.2  Peak Current Mode Control
      3. 7.3.3  Switching Frequency and Synchronization
      4. 7.3.4  Current Sense and Current Limit
      5. 7.3.5  Average LED Current
      6. 7.3.6  Precision Reference (VREF)
      7. 7.3.7  Low-Level Analog Dimming
      8. 7.3.8  Soft-Start and Shutdown
      9. 7.3.9  VCC Regulator and Start-Up
      10. 7.3.10 Overvoltage Protection (OVP)
      11. 7.3.11 Input Undervoltage Lockout (UVLO)
      12. 7.3.12 PWM Dimming
      13. 7.3.13 Control Loop Compensation
      14. 7.3.14 Thermal Shutdown
    4. 7.4 Device Functional Modes
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Inductor
      2. 8.1.2 LED Dynamic Resistance
      3. 8.1.3 Output Capacitor
      4. 8.1.4 Input Capacitor
      5. 8.1.5 MOSFET Selection
      6. 8.1.6 Recirculating Diode
    2. 8.2 Typical Applications
      1. 8.2.1 Basic Topology Schematics
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1  Operating Point
          2. 8.2.1.2.2  Switching Frequency
          3. 8.2.1.2.3  Average LED Current
          4. 8.2.1.2.4  Inductor Ripple Current
          5. 8.2.1.2.5  Output Capacitance
          6. 8.2.1.2.6  Peak Current Limit
          7. 8.2.1.2.7  Loop Compensation
          8. 8.2.1.2.8  Input Capacitance
          9. 8.2.1.2.9  NFET
          10. 8.2.1.2.10 Diode
          11. 8.2.1.2.11 Input UVLO
          12. 8.2.1.2.12 Output OVLO
        3. 8.2.1.3 Application Curve
      2. 8.2.2 Simplified Application
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
          1. 8.2.2.2.1  Operating Point
          2. 8.2.2.2.2  Switching Frequency
          3. 8.2.2.2.3  Average LED Current
          4. 8.2.2.2.4  Inductor Ripple Current
            1. 8.2.2.2.4.1 Minimum Inductor Value
            2. 8.2.2.2.4.2 Inductor Ripple Current
            3. 8.2.2.2.4.3 RMS Inductor Current
          5. 8.2.2.2.5  LED Ripple Current
            1. 8.2.2.2.5.1 Output Capacitor
            2. 8.2.2.2.5.2 Output Capacitor RMS Current
          6. 8.2.2.2.6  Peak Current Limit
          7. 8.2.2.2.7  Loop Compensation
            1. 8.2.2.2.7.1 Compensation Capacitor
            2. 8.2.2.2.7.2 RHP Zero
            3. 8.2.2.2.7.3 Output Capacitor Pole
          8. 8.2.2.2.8  Input Capacitance
          9. 8.2.2.2.9  NFET
            1. 8.2.2.2.9.1 Maximum Average NFET Current
            2. 8.2.2.2.9.2 RMS Transistor Current
          10. 8.2.2.2.10 Diode
            1. 8.2.2.2.10.1 Maximum Average Diode Current
          11. 8.2.2.2.11 Output OVLO
          12. 8.2.2.2.12 Input UVLO
          13. 8.2.2.2.13 Soft-Start
          14. 8.2.2.2.14 PWM Dimming Method
          15. 8.2.2.2.15 Analog Dimming Method
  9. 9 Power Supply Recommendations
    1. 9.1 Bench Supply Current Limit
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Community Resources
    2. 11.2 Trademarks
    3. 11.3 Electrostatic Discharge Caution
    4. 11.4 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

9 Power Supply Recommendations

9.1 Bench Supply Current Limit

It is important to set the output current limit of your input supply to an appropriate value to avoid delays in your converter analysis and optimization. If not set high enough, current limit can be tripped during start up or when your converter output power is increased, causing a foldback or shut-down condition. It is a common oversight when powering up a converter for the first time.