JAJSFV5C July   2018  – March 2022 UCC24624

PRODUCTION DATA  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
  4. 4 Revision History
  5. 5 概要 (続き)
  6. 6 Pin Configuration and Functions
    1.     Pin Functions
  7. 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. 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. 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

8.3.4.1 On-Time Blanking

Right after the SR MOSFET turn on, the SR is driven fully on. For the LLC resonant converter, the SR current rises from zero. It is desired to keep the SR on during this situation and allow the current to rise to a high enough level to maintain the full conduction time. In UCC24624, after the SR is turned on, a minimum on time blanking of 475 ns is implemented. During the on-time blanking time, the SR keeps conducting regardless of its drain to source voltage. This on-time blanking limits the maximum switching frequency of the LLC converter to 625 kHz.