SLVSGH1B April   2023  – February 2025 TPS923652 , TPS923653 , TPS923654 , TPS923655

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
  7. 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
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Adaptive Off-Time Current Mode Control
        1. 7.3.1.1 Switching Frequency Settings
        2. 7.3.1.2 Spread Spectrum
      2. 7.3.2 Setting LED Current
      3. 7.3.3 Undervoltage Lockout
      4. 7.3.4 Internal Soft Start
      5. 7.3.5 Dimming Mode
        1. 7.3.5.1 PWM Dimming
        2. 7.3.5.2 Analog Dimming
        3. 7.3.5.3 Hybrid Dimming
        4. 7.3.5.4 Flexible Dimming
      6. 7.3.6 CC/CV Charging Mode
      7. 7.3.7 Fault Protection
      8. 7.3.8 Thermal Foldback
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 TPS923654 Boost, 12V Input, 1A Output, 12-piece WLED Driver With Analog Dimming
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Inductor Selection
          2. 8.2.1.2.2 Input Capacitor Selection
          3. 8.2.1.2.3 Output Capacitor Selection
          4. 8.2.1.2.4 Sense Resistor Selection
          5. 8.2.1.2.5 Other External Components Selection
        3. 8.2.1.3 Application Curves
      2. 8.2.2 TPS923654 Buck-Boost, 24V Input, 2A Output, 4-piece WLED Driver with PWM Dimming
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
          1. 8.2.2.2.1 Inductor Selection
          2. 8.2.2.2.2 Input Capacitor Selection
          3. 8.2.2.2.3 Output Capacitor Selection
          4. 8.2.2.2.4 Sense Resistor Selection
          5. 8.2.2.2.5 Other External Components Selection
        3. 8.2.2.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Receiving Notification of Documentation Updates
    2. 9.2 Support Resources
    3. 9.3 Trademarks
    4. 9.4 Electrostatic Discharge Caution
    5. 9.5 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information
8.2.1.2.5 Other External Components Selection

In this design, a 100Ω, 0603 resistor is recommended for RFLT at CSN pin to avoid noise injection and increase robustness. An optional 1nF, 50V X7R ceramic capacitor is chosen for CFLT across CSP-CSN pins to filter high-frequency noise of sense feedback. Using Equation 11, a 10µF, 50V X7R ceramic capacitor is chosen for CSENSE to suppress the ac magnitude of sense feedback less than 200mV.

Equation 11. C S E N S E =     0.25 × I L ( m a x ) 200 m V × f S W

For loop stability, it is recommended to select a 1nF, 10V X7R ceramic capacitor for CCOMP and an optional 100Ω resistor for RCOMP. An optional 1MΩ resistor is chosen for RDAMP to suppress the overshoot current at startup.