SLUSC82B April   2017  – July 2026 UCC24630

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Timing Requirements
    7. 5.7 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Start Up and UVLO
      2. 6.3.2 Volt-Sec SR Driver On-Time Control
      3. 6.3.3 CCM Dead Time
      4. 6.3.4 Standby Operation
      5. 6.3.5 Pin Fault Protection
        1. 6.3.5.1 VPC Pin Overvoltage
        2. 6.3.5.2 VPC Pin Open
        3. 6.3.5.3 VSC Pin Open
        4. 6.3.5.4 TBLK Pin Open
        5. 6.3.5.5 VPC and VSC Short to Ground
        6. 6.3.5.6 TBLK Pin Short to Ground
    4. 6.4 Device Functional Modes
      1. 6.4.1 Start-Up
      2. 6.4.2 Normal Operation
      3. 6.4.3 Standby Operation
      4. 6.4.4 Conditions to Stop Operation
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 AC-to-DC Adapter, 19.5V, 65W
      2. 7.2.2 Design Requirements
      3. 7.2.3 Calculation of Component Values
        1. 7.2.3.1 VPC Input
        2. 7.2.3.2 VSC Input
        3. 7.2.3.3 TBLK Input
      4. 7.2.4 Application Curves
    3. 7.3 Best Design Practices
    4. 7.4 Power Supply Recommendations
    5. 7.5 Layout
      1. 7.5.1 Layout Guidelines
        1. 7.5.1.1 VDD Pin
        2. 7.5.1.2 VPC Pin
        3. 7.5.1.3 VSC Pin
        4. 7.5.1.4 GND Pin
        5. 7.5.1.5 TBLK Pin
        6. 7.5.1.6 DRV Pin
      2. 7.5.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Device Nomenclature
        1. 8.1.1.1 Definition of Terms
    2. 8.2 Receiving Notification of Documentation Updates
    3. 8.3 Support Resources
    4. 8.4 Trademarks
    5. 8.5 Electrostatic Discharge Caution
    6. 8.6 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

6.3.4 Standby Operation

To minimize power consumption at very light load and standby conditions, the UCC24630 disables the SR DRV output and enters a low current operating state. The criteria for operating in standby mode or normal operation are determined by the average frequency detected on the VPC pin. The frequency detection is compatible with burst mode operation or continuous low frequency FM operation. At start-up, the device is in normal operation to enable DRV to the SR MOSFET. If < 64 cycles occur in tENTO, 12.8ms typical, the device disables the DRV output and enters low-current operating mode with bias current of ISTBY. In standby mode the criteria to enter normal operating mode is when > 32 cycles occur within tEN, 2.56ms typical. The device enters normal operation as soon as the 32 cycles occur to reduce the response time exiting standby operation. The average frequency of entering standby mode is 5kHz typical, and the average frequency of exiting standby mode is 12.5kHz typical. Refer to Figure 6-10 for an illustration of standby mode timing.

UCC24630 Standby Mode OperationFigure 6-10 Standby Mode Operation