SLUSEM9A September   2022  – June 2024 UCC21755-Q1

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  Power Ratings
    6. 5.6  Insulation Specifications
    7. 5.7  Safety Limiting Values
    8. 5.8  Electrical Characteristics
    9. 5.9  Switching Characteristics
    10. 5.10 Insulation Characteristics Curves
    11. 5.11 Typical Characteristics
  7. 6 Parameter Measurement Information
    1. 6.1 Propagation Delay
      1. 6.1.1 Non-Inverting and Inverting Propagation Delay
    2. 6.2 Input Deglitch Filter
    3. 6.3 Active Miller Clamp
      1. 6.3.1 Internal On-Chip Active Miller Clamp
    4. 6.4 Undervoltage Lockout (UVLO)
      1. 6.4.1 VCC UVLO
      2. 6.4.2 VDD UVLO
    5. 6.5 Desaturation (DESAT) Protection
      1. 6.5.1 DESAT Protection with Soft Turn-OFF
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Power Supply
      2. 7.3.2  Driver Stage
      3. 7.3.3  VCC and VDD Undervoltage Lockout (UVLO)
      4. 7.3.4  Active Pulldown
      5. 7.3.5  Short Circuit Clamping
      6. 7.3.6  Internal Active Miller Clamp
      7. 7.3.7  Desaturation (DESAT) Protection
      8. 7.3.8  Soft Turn-Off
      9. 7.3.9  Fault (FLT), Reset and Enable (RST/EN)
      10. 7.3.10 Isolated Analog to PWM Signal Function
    4. 7.4 Device Functional Modes
  9. 8 Applications 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
        1. 8.2.2.1 Input Filters for IN+, IN-, and RST/EN
        2. 8.2.2.2 PWM Interlock of IN+ and IN-
        3. 8.2.2.3 FLT, RDY, and RST/EN Pin Circuitry
        4. 8.2.2.4 RST/EN Pin Control
        5. 8.2.2.5 Turn-On and Turn-Off Gate Resistors
        6. 8.2.2.6 Overcurrent and Short Circuit Protection
        7. 8.2.2.7 Isolated Analog Signal Sensing
          1. 8.2.2.7.1 Isolated Temperature Sensing
          2. 8.2.2.7.2 Isolated DC Bus Voltage Sensing
        8. 8.2.2.8 Higher Output Current Using an External Current Buffer
      3. 8.2.3 Application Curves
  10. 9 Power Supply Recommendations
  11. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  12. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Support Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  13. 12Revision History
  14. 13Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7.3.8 Soft Turn-Off

The device initiates a soft turn-off when the overcurrent and short circuit protection are triggered. When the overcurrent and short circuit faults occur, the IGBT transits from the active region to the desaturation region very quickly. The channel current is controlled by the gate voltage and decreases softly; thus, the overshoot of the IGBT is limited and prevents the overvoltage breakdown. There is a tradeoff between the overshoot voltage and short circuit energy. The turn-off speed should be slow to limit the overshoot-voltage, but the shutdown time should not be too long that the large energy dissipation can breakdown the device. The 400-mA soft turn-off current of the device ensures the power switches are safely turned off during short circuit events. Figure 6-10 shows the soft turn-off timing diagram.

UCC21755-Q1 Soft Turn-OffFigure 7-6 Soft Turn-Off