SLUSAO7C September   2011  – July 2024 UCC28063

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  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  Principles of Operation
      2. 7.3.2  Natural Interleaving
      3. 7.3.3  On-Time Control, Maximum Frequency Limiting, and Restart Timer
      4. 7.3.4  Distortion Reduction
      5. 7.3.5  Zero-Current Detection and Valley Switching
      6. 7.3.6  Phase Management and Light-Load Operation
      7. 7.3.7  External Disable
      8. 7.3.8  Improved Error Amplifier
      9. 7.3.9  Soft Start
      10. 7.3.10 Brownout Protection
      11. 7.3.11 Dropout Detection
      12. 7.3.12 VREF
      13. 7.3.13 VCC
      14. 7.3.14 Control of Downstream Converter
      15. 7.3.15 System Level Protections
        1. 7.3.15.1 Failsafe OVP - Output Overvoltage Protection
        2. 7.3.15.2 Overcurrent Protection
        3. 7.3.15.3 Open-Loop Protection
        4. 7.3.15.4 VCC Undervoltage Lock-Out (UVLO) Protection
        5. 7.3.15.5 Phase-Fail Protection
        6. 7.3.15.6 CS-Open, TSET-Open and -Short Protection
        7. 7.3.15.7 Thermal Shutdown Protection
        8. 7.3.15.8 AC-Line Brownout and Dropout Protections
        9. 7.3.15.9 Fault Logic Diagram
    4. 7.4 Device Functional Modes
  9. 8 Applications 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  Inductor Selection
        2. 8.2.2.2  ZCD Resistor Selection (RZA, RZB)
        3. 8.2.2.3  HVSEN
        4. 8.2.2.4  Output Capacitor Selection
        5. 8.2.2.5  Selecting (RS) For Peak Current Limiting
        6. 8.2.2.6  Power Semiconductor Selection (Q1, Q2, D1, D2)
        7. 8.2.2.7  Brownout Protection
        8. 8.2.2.8  Converter Timing
        9. 8.2.2.9  Programming VOUT
        10. 8.2.2.10 Voltage Loop Compensation
      3. 8.2.3 Application Curves
        1. 8.2.3.1 Input Ripple Current Cancellation with Natural Interleaving
        2. 8.2.3.2 Brownout Protection
  10. 9 Power Supply Recommendations
  11. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  12. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Development Support
        1. 11.1.1.1 Related Parts
      2. 11.1.2 Device Nomenclature
        1. 11.1.2.1 Detailed Pin Description
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  13. 12Mechanical, Packaging, and Orderable Information

7.3.15.5 Phase-Fail Protection

The UCC28063 detects failure of either of the phases by monitoring the sequence of ZCD pulses. During normal two-phase operation, if one ZCD input remains idle for longer than approximately 12 ms while the other ZCD input switches normally, the over-current threshold is reduced and PWMCNTL goes to a high-impedance state, indicating that the PFC power stage is not operating correctly. During normal single-phase operation (PHB < 0.8 V), phase failure is not monitored. Also on the UCC28063, phase failure is not monitored when COMP is below approximately 222 mV.