SLUSFK1E January   2024  – February 2025 UCC33420

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison
  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  Power Ratings
    6. 6.6  Insulation Specifications
    7. 6.7  Safety-Related Certifications
    8. 6.8  Safety Limiting Values
    9. 6.9  Electrical Characteristics
    10. 6.10 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 Enable and Disable
      2. 7.3.2 Output Voltage Soft-Start
      3. 7.3.3 Output Voltage Steady-State Regulation
      4. 7.3.4 Protection Features
        1. 7.3.4.1 Input Under-Voltage and Over-Voltage Lockout
        2. 7.3.4.2 Output Under-Voltage Protection
        3. 7.3.4.3 Output Over-Voltage Protection
        4. 7.3.4.4 Over-Temperature Protection
        5. 7.3.4.5 Fault Reporting and Auto-Restart
      5. 7.3.5 VCC Load Recommended Operating Area
      6. 7.3.6 Electromagnetic Compatibility (EMC) Considerations
    4. 7.4 Device Functional Modes
  9. 8 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. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Third-Party Products Disclaimer
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 Receiving Notification of Documentation Updates
    4. 9.4 Support Resources
    5. 9.5 Trademarks
    6. 9.6 Electrostatic Discharge Caution
    7. 9.7 Glossary
  11. 10Revision History
  12. 11Mechanical and Packaging Information

6.8 Safety Limiting Values

Safety limiting(1) intends to minimize potential damage to the isolation barrier upon failure of input or output circuitry. A failure of the I/O can allow low resistance to ground or the supply and, without current limiting, dissipate sufficient power to over-heat the die and damage the isolation barrier potentially leading to secondary system failures.
PARAMETER TEST CONDITIONS MAX UNIT
IS Safety input,  output or supply current RθJA = 59.7°C/W, VVINP = 5.5V, TJ = 150°C, TA = 25°C, POUT = 2.4W  817 mA
RθJA = 59.7°C/W, VVINP = 4.5V, TJ = 150°C, TA = 25°C, POUT = 1.65W  832 mA
PS Safety power dissipation (input power - output power) RθJA = 59.7 °C/W, TJ = 150 °C, TA = 25 °C 2.1 W
TS Safety temperature 150 °C
(1) The maximum safety temperature, TS, has the same value as the maximum junction temperature, TJ, specified for the device. The IS and PS parameters represent the safety current and safety power respectively. The maximum limits of IS and PS should not be exceeded. These limits vary with the ambient temperature, TA.
The junction-to-air thermal resistance, RθJA, in the Thermal Information table is that of a device installed on a high-K test board for leaded surface-mount packages. Use these equations to calculate the value for each parameter:
TJ = TA + RqJA × P, where P is the power dissipated in the device.
TJ(max) = TS = TA + RθJA × PS, where TJ(max) is the maximum allowed junction temperature.
PS = IS × VVINP, where VVINP is the maximum input voltage.