SLUSDM7A April   2020  – May 2020 UCC21736-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Pin Configuration
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 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 Switching Characteristics
    11. 6.11 Insulation Characteristics Curves
    12. 6.12 Typical Characteristics
  7. 7 Parameter Measurement Information
    1. 7.1 Propagation Delay
      1. 7.1.1 Regular Turn-OFF
    2. 7.2 Input Deglitch Filter
    3. 7.3 Active Miller Clamp
      1. 7.3.1 External Active Miller Clamp
    4. 7.4 Under Voltage Lockout (UVLO)
      1. 7.4.1 VCC UVLO
      2. 7.4.2 VDD UVLO
      3. 7.4.3 VEE UVLO
    5. 7.5 OC (Over Current) Protection
      1. 7.5.1 OC Protection with Soft Turn-OFF
    6. 7.6 ASC Protection
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Power Supply
      2. 8.3.2 Driver Stage
      3. 8.3.3 VCC, VDD and VEE Undervoltage Lockout (UVLO)
      4. 8.3.4 Active Pulldown
      5. 8.3.5 Short Circuit Clamping
      6. 8.3.6 External Active Miller Clamp
      7. 8.3.7 Overcurrent and Short Circuit Protection
      8. 8.3.8 Fault (FLT, Reset and Enable (RST/EN)
      9. 8.3.9 ASC Protection and APWM Monitor
    4. 8.4 Device Functional Modes
  9. 9 Applications and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Input filters for IN+, IN- and RST/EN
        2. 9.2.2.2 PWM Interlock of IN+ and IN-
        3. 9.2.2.3 FLT, RDY and RST/EN Pin Circuitry
        4. 9.2.2.4 RST/EN Pin Control
        5. 9.2.2.5 Turn on and turn off gate resistors
        6. 9.2.2.6 External Active Miller Clamp
        7. 9.2.2.7 Overcurrent and Short Circuit Protection
          1. 9.2.2.7.1 Protection Based on Power Modules with Integrated SenseFET
          2. 9.2.2.7.2 Protection Based on Desaturation Circuit
          3. 9.2.2.7.3 Protection Based on Shunt Resistor in Power Loop
        8. 9.2.2.8 Higher Output Current Using an External Current Buffer
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 Receiving Notification of Documentation Updates
    3. 12.3 Community Resource
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

9.2.2.7.3 Protection Based on Shunt Resistor in Power Loop

In lower power applications, to simplify the circuit and reduce the cost, a shunt resistor can be used in series in the power loop and measure the current directly. Since the resistor is in series in the power loop, it directly measures the current and can have high accuracy by using a high precision resistor. The resistance needs to be small to reduce the power loss, and should have large enough voltage resolution for the protection. Since the sensing resistor is also in series in the gate driver loop, the voltage drop on the sensing resistor can cause the voltage drop on the gate voltage of the IGBT or SiC MOSFET modules. The parasitic inductance of the sensing resistor and the PCB trace of the sensing loop will also cause a noise voltage source during switching transient, which makes the gate voltage oscillate. Thus, this method is not recommended for high power application, or when dI/dt is high. To use it in low power application, the shunt resistor loop should be designed to have the optimal voltage drop and minimum noise injection to the gate loop.

UCC21736-Q1 OC-Protection-block-shunt-resistor.gifFigure 53. Overcurrent and Short Circuit Protection Based on Shunt Resistor