SGLS183C August   2003  – July 2025 UCC2808A-1Q1 , UCC2808A-2Q1

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Device Comparison Table
  6. Pin Configurations and Functions
  7. 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. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Pin Descriptions
        1. 7.3.1.1 COMP Pin
        2. 7.3.1.2 OUTA and OUTB Pins
        3. 7.3.1.3 RC Pin
        4. 7.3.1.4 VDD Pin
    4. 7.4 Device Functional Modes
      1. 7.4.1 VCC
      2. 7.4.2 Push-Pull or Half-Bridge Function
  9. Application 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
      3. 8.2.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. Device and Documentation Support
    1. 9.1 Documentation Support
      1. 9.1.1 Related Documentation
    2. 9.2 Support Resources
    3. 9.3 Trademarks
    4. 9.4 Electrostatic Discharge Caution
    5. 9.5 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

VDD Pin

The VDD pin is the power input connection for UCC2808A-xQ1. Although quiescent VDD current is very low, total supply current is higher. The total supply current depends on OUTA and OUTB current and the programmed oscillator frequency. Total VDD current is the sum of quiescent VDD current and the average OUT current. With a known operating frequency and the MOSFET gate charge (Qg), the average OUT current is calculated from:

Equation 2. IOUT=Qg×F

where

  • F = frequency

To prevent noise problems, bypass VDD to GND with a ceramic capacitor as close to the chip as possible, along with an electrolytic capacitor. A 1μF decoupling capacitor is recommended.