SLUAAY2 December   2024 ISO5451 , ISO5451-Q1 , ISO5452 , ISO5452-Q1 , ISO5851 , ISO5851-Q1 , ISO5852S , ISO5852S-EP , ISO5852S-Q1 , UCC21710 , UCC21710-Q1 , UCC21717-Q1 , UCC21732 , UCC21732-Q1 , UCC21736-Q1 , UCC21737-Q1 , UCC21738-Q1 , UCC21739-Q1 , UCC21750 , UCC21750-Q1 , UCC21755-Q1 , UCC21756-Q1 , UCC21759-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1 Introduction
  5. 2 SiC and IGBT Characteristics
  6. 3 Failure Modes
  7. 4 Short-Circuit Protection Approaches
    1. 4.1 Short-Circuit Current-Based Protection Implementation
    2. 4.2 Short Circuit Voltage-Based Protection Implementation
  8. 5 DESAT Circuitry Design
    1. 5.1 DESAT Circuit Component Selection
    2. 5.2 Effect of Parasitic Elements
    3. 5.3 Effect of Rlim on DESAT Noise
  9. 6 Safe Shutdown
    1. 6.1 Safe Shutdown Mechanisms
    2. 6.2 Safe Shutdown Considerations
  10. 7 Short-Circuit Test Setup and Data
    1. 7.1 Short-Circuit Bench Measurement Setup
    2. 7.2 SC Board Setup for Data Collection
    3. 7.3 Different Circuit Configurations for SC Testing
    4. 7.4 Bench Measurement Results
    5. 7.5 Overall Summary of SiC vs IGBT Power Module SC Observation
  11. 8 Key Consideration in Designing SC Protection Circuit
  12. 9 Summary
  13. 10References

7.3 Different Circuit Configurations for SC Testing

Two different DESAT circuit implementations and “OC as DESAT” circuit implementation are used with two different turn-off approaches to compare the SC performance for IGBT and SiC power modules.

  • Circuit Implementation for DESAT without external charge:
    • Charge current: 0.5mA typical
    • DESAT detection Threshold: 9V
    • Capacitor updated to 50pF
    UCC21750Q1 DESAT Without External Charge Implementation Figure 7-4 DESAT Without External Charge Implementation
  • Circuit Implementation for DESAT with external charge from OUTH:
    • Charge current: 0.5mA +10mA typical
    • DESAT detection Threshold: 9V
    • Capacitor updated to 50pF
    UCC21750Q1 DESAT With External Charge Implementation Figure 7-5 DESAT With External Charge Implementation
  • Circuit Implementation for OC as DESAT with external charge from OUTH:
    • Charge current: <10mA Typical
    • OC detection Threshold: 0.7V
    • Capacitor updated to 50pF
    UCC21750Q1 OC as DESAT Implementation Figure 7-6 OC as DESAT Implementation