SNVSBO5B December   2019  – May 2021 UCC12040

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  Power Ratings
    6. 6.6  Insulation Specifications
    7. 6.7  Safety-Related Certifications
    8. 6.8  Safety Limiting Values
    9. 6.9  Electrical Characteristics
    10. 6.10 Switching Characteristics
    11. 6.11 Insulation Characteristics Curves
    12. 6.12 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 Enable and Disable
      2. 7.3.2 UVLO, Power-Up, and Power-Down Behavior
      3. 7.3.3 VISO Load Recommended Operating Area
      4. 7.3.4 Thermal Shutdown
      5. 7.3.5 External Clocking and Synchronization
      6. 7.3.6 VISO Output Voltage Selection
      7. 7.3.7 Electromagnetic Compatibility (EMC) Considerations
    4. 7.4 Device Functional Modes
  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 VISO Output Capacitor Selection
      3. 8.2.3 Application Curves
  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 Development Support
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Support Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  12. 12Mechanical and Packaging Information

Package Options

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

7.3.3 VISO Load Recommended Operating Area

Figure 7-1 depicts the device VISO regulation behavior across the output load range, including when the output is overloaded. For proper device operation, ensure that the device VISO output load does not exceed the maximum output current (IOUT_MAX). The value for IOUT_MAX over different temperature and VINP conditions are shown from Figure 6-8 to Figure 6-11. The following protection mechanisms will be engaged if the UCC12040 is loaded beyond the recommended operating area:

  1. The device limits the maximum output power. If a load exceeding IOUT_MAX is applied, VISO drops accordingly to meet the maximum power limit.
  2. If VISO drops below nominal 3.8 V while operating in the constant power limit region, the over-power fold-back feature will switch the power converter from active rectification to passive rectification, and the built-in recovery hysteresis will ensure the UCC12040 recovers at a lower output power. The device returns to active rectification when load drops and VISO increases above nominal 4.3V.
  3. The device triggers a soft-start reset if VISO drops below the nominal 1.8-V threshold. This reset is designed to protect the device during VISO short-circuit conditions.
  4. Thermal shutdown protection disables the converter if the device is operated in any of the above regions long enough to raise the silicon junction temperature above the thermal shutdown threshold. See the Section 7.3.4 section for more details on this device feature.
GUID-EA42C412-D9D1-4967-945F-8EE812CA0B9D-low.gifFigure 7-1 VISO Load Recommended Operating Area Description