SLUSEV9A August   2023  – September 2023 UCC14340-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Device Comparison
  7. 6 Pin Configuration and Functions
  8. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Insulation Specifications
    6. 7.6 Safety-Related Certifications
    7. 7.7 Electrical Characteristics
    8. 7.8 Safety Limiting Values
    9. 7.9 Typical Characteristics
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Power Stage Operation
        1. 8.3.1.1 VDD-VEE Voltage Regulation
        2. 8.3.1.2 COM-VEE Voltage Regulation
        3. 8.3.1.3 Power Handling Capability
      2. 8.3.2 Output Voltage Soft Start
      3. 8.3.3 ENA and PG
      4. 8.3.4 Protection Functions
        1. 8.3.4.1 Input Undervoltage Lockout
        2. 8.3.4.2 Input Overvoltage Lockout
        3. 8.3.4.3 Output Undervoltage Protection
        4. 8.3.4.4 Output Overvoltage Protection
        5. 8.3.4.5 Overpower Protection
        6. 8.3.4.6 Overtemperature Protection
    4. 8.4 Device Functional Modes
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Capacitor Selection
        2. 9.2.2.2 Single RLIM Resistor Selection
        3. 9.2.2.3 RDR Circuit Component Selection
        4. 9.2.2.4 Feedback Resistors Selection
  11. 10System Examples
  12. 11Power Supply Recommendations
  13. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  14. 13Device and Documentation Support
    1. 13.1 Documentation Support
      1. 13.1.1 Related Documentation
    2. 13.2 Receiving Notification of Documentation Updates
    3. 13.3 Support Resources
    4. 13.4 Trademarks
    5. 13.5 Electrostatic Discharge Caution
    6. 13.6 Glossary
  15. 14Mechanical, Packaging, and Orderable Information
  16. 15Tape and Reel Information

Package Options

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

8.3.4.1 Input Undervoltage Lockout

UCC14340-Q1 can take wide input voltage range, from 13.5 V to 16.5 V. When the input voltage becomes too low, the output either cannot be regulated due to the transformer turns ratio limitation, or the converter operates with too much current stress. Either way, the converter must shut down to protect the system.

The UCC14340-Q1 enters input undervoltage lockout when VVIN voltage becomes lower than the UVLO threshold VVIN_UVLOP_FALLING. In UVLO mode, the converter stops switching. After VIN pin voltage becomes lower than the RESET falling threshold VVIN_RESET_FALLING , UCC14340-Q1 resets all the protections. After that, after the VVIN voltage becomes above the UVLO threshold VVIN_UVLOP_RISING, the converter is enabled. Depending on the ENA pin voltage, the converter can start switching, go through the soft-start process, or in the disable mode, waiting for ENA pin voltage becomes high.