SLUUD68 December   2024

 

  1.   1
  2.   Abstract
  3. 13
  4. 1General TI High Voltage Evaluation User Safety Guidelines
  5. 2Module Compatibility
    1. 2.1 Supported Wolfspeed Modules and Evaluation Platforms
  6. 3System Overview and Functions
    1. 3.1 Features
    2. 3.2 Specifications
    3. 3.3 PCB Pinout
    4. 3.4 Device Information
      1. 3.4.1 Primary-Side Power
      2. 3.4.2 Primary-Side I/O and Diagnostics
      3. 3.4.3 Secondary-Side Bias Supply
      4. 3.4.4 Output Stage Gate Loop
      5. 3.4.5 Short-Circuit Detection - DESAT
  7. 4Using the EVM
    1. 4.1 Equipment List
    2. 4.2 Test Setups and Procedures
      1. 4.2.1 Power-On and Bias Supply Check
      2. 4.2.2 Output Switching
  8. 5EVM Example Measurements
    1. 5.1 DESAT Functionality Testing
  9. 6EVM Tuning
    1. 6.1 Adjust Power Supplies
      1. 6.1.1 Adjust Only VDD Bias Supply
      2. 6.1.2 Adjust VDD and VEE Bias Supplies Simultaneously
      3. 6.1.3 Switch to Unipolar Bias Supply
      4. 6.1.4 Bypass VDD LDO
    2. 6.2 Adjust Drive Strength
    3. 6.3 Adjust Soft Turn-off Strength
  10. 7Hardware Design Files
    1. 7.1 Schematics
    2. 7.2 PCB Layouts
    3. 7.3 Bill of Materials (BOM)
  11. 8Additional Information
    1. 8.1 Trademarks
  12. 9Revision History

5.1 DESAT Functionality Testing

UCC2189X5YQEVM-096 DESAT and Soft Turn-Off WaveformFigure 5-1 DESAT and Soft Turn-Off Waveform.

This test is carried out without a bus voltage to test the functionality of DESAT pin, soft turn-off, and nFLT feedback.

The voltage on DESAT first reaches the detection threshold. After a short delay as specified in the UCC2189X5Y-Q1 data sheet, output experiences soft turn-off via the SSD pin. The soft turn-off current can be programmed by the resistor on SSD. On the primary side, nFLT also pulls low as a result of DESAT triggering, following a longer delay as specified in the datasheet.