ZHCSIL2C July   2018  – March 2022 UCC24624

PRODUCTION DATA  

  1. 特性
  2. 应用
  3. 说明
  4. Revision History
  5. 说明(续)
  6. Pin Configuration and Functions
    1.     Pin Functions
  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 Electrical Characteristics
    6. 7.6 Timing Requirements
    7. 7.7 Typical Characteristics
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Power Management
      2. 8.3.2 Synchronous Rectifier Control
      3. 8.3.3 Turn-off Threshold Adjustment
      4. 8.3.4 Noise Immunity
        1. 8.3.4.1 On-Time Blanking
        2. 8.3.4.2 Off-Time Blanking
        3. 8.3.4.3 Two-Channel Interlock
        4. 8.3.4.4 SR Turn-on Re-arm
        5. 8.3.4.5 Adaptive Turn-on Delay
      5. 8.3.5 Gate Voltage Clamping
      6. 8.3.6 Standby Mode
    4. 8.4 Device Functional Modes
      1. 8.4.1 UVLO Mode
      2. 8.4.2 Standby Mode
      3. 8.4.3 Run Mode
  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 MOSFET Selection
        2. 9.2.2.2 Snubber Design
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Development Support
        1. 12.1.1.1 Custom Design With WEBENCH® Tools
    2. 12.2 Receiving Notification of Documentation Updates
    3. 12.3 Community Resources
    4. 12.4 Trademarks

UVLO Mode

UCC24624 uses the REG pin voltage to detect UVLO instead of the VDD pin voltage. When the REG voltage has not yet reached the VREGON threshold, or has fallen below the UVLO threshold VREGOFF, the device operates in the low-power UVLO mode. In this mode, most internal functions are disabled and VDD current is IVDDSTART. If the REG pin is above 2 V, there is an active pull down from VG1 and VG2 to PGND to prevent the SR from falsely turning on due to noise. When the REG pin voltage is less than 2 V, there is a weak pull down from VG1 and VG2 to PGND and this also prevents noise from turning on SR MOSFETs. The device exits UVLO mode when REG increases above the VREGON threshold.