SLUSFN2B May   2024  – December 2024 TPS513885

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1  PWM Operation and D-CAP3™ Control Mode
      2. 6.3.2  VCC Switchover Function
      3. 6.3.3  Soft Start
      4. 6.3.4  Large Duty Operation
      5. 6.3.5  Power Good
      6. 6.3.6  Overcurrent Protection and Undervoltage Protection
      7. 6.3.7  Overvoltage Protection
      8. 6.3.8  UVLO Protection
      9. 6.3.9  Output Voltage Discharge
      10. 6.3.10 Thermal Shutdown
    4. 6.4 Device Functional Modes
      1. 6.4.1 Light Load Operation
      2. 6.4.2 Advanced Eco-mode Control
      3. 6.4.3 Out-of-Audio™ Mode
      4. 6.4.4 Mode Selection
      5. 6.4.5 Standby Operation
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
        1. 7.2.2.1 Custom Design With WEBENCH® Tools
        2. 7.2.2.2 External Component Selection
          1. 7.2.2.2.1 VOUT and FB Pin Configuration
          2. 7.2.2.2.2 MODE Selection
          3. 7.2.2.2.3 Inductor Selection
          4. 7.2.2.2.4 Output Capacitor Selection
          5. 7.2.2.2.5 Input Capacitor Selection
      3. 7.2.3 Application Curves
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Development Support
        1. 8.1.1.1 Custom Design With WEBENCH® Tools
    2. 8.2 Documentation Support
      1. 8.2.1 Related Documentation
    3. 8.3 Receiving Notification of Documentation Updates
    4. 8.4 Support Resources
    5. 8.5 Trademarks
    6. 8.6 Electrostatic Discharge Caution
    7. 8.7 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

6.4.3 Out-of-Audio™ Mode

Out-of-Audio (OOA) mode is a unique control feature that keeps the switching frequency above audible frequency with minimum reduction in efficiency. This mode prevents audio noise generation from the output capacitors and inductor. During Out-of-Audio operation, the OOA control circuit monitors the states of both high-side and low-side MOSFETs and forces them to switch. When both high-side and low-side MOSFETs are off for more than 30μs during a light-load condition, the low-side FET discharges until output voltage drops to trigger the high-side FET on or inductor current hits negative OC limit.

If the EN pin is selected to operate in OOA mode, when the device works at light load, the minimum switching frequency is above 20kHz, which avoids the audible noise in the system. When the device works in OOA mode, TI recommends setting the valley value of inductor current above –3A by choosing the appropriate inductor.