TIDUF31B May   2023  – September 2024

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
    1. 1.1 Key System Specifications
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
    3. 2.3 Highlighted Products
      1. 2.3.1 MSPM0G1507
      2. 2.3.2 UCC28881
      3. 2.3.3 UCC27712
      4. 2.3.4 TLV9064
      5. 2.3.5 TPS54202
  9. 3System Design Theory
    1. 3.1  High-Voltage Buck Auxiliary Power Supply
    2. 3.2  DC Bus Voltage Sensing
    3. 3.3  Motor Drive Stage
    4. 3.4  Bypass Capacitors
    5. 3.5  Phase Current Sensing With Two or Three Shunt Resistors
    6. 3.6  Phase Current Sensing With a Single Shunt Resistor
    7. 3.7  Hall-Effect Sensor or QEI Interface for Sensored Motor Control
    8. 3.8  DAC for Software Debug
    9. 3.9  Overcurrent Protection
    10. 3.10 Overtemperature Protection
    11. 3.11 Isolated UART port
    12. 3.12 Inverter Peak Power Capability
  10. 4Hardware, Software, Testing Requirements, and Test Results
    1. 4.1 Hardware Requirements
      1. 4.1.1 Hardware Board Overview
      2. 4.1.2 Test Equipment for Board Validation
    2. 4.2 Software Requirements
      1. 4.2.1 Getting Started MSPM0 Firmware
        1. 4.2.1.1 Download and Install Software Required for Board Test
        2. 4.2.1.2 Import the Project Into CCS
        3. 4.2.1.3 Compile the Project
        4. 4.2.1.4 Download Image and Spin Motor
    3. 4.3 Test Results
      1. 4.3.1 Test Setup
      2. 4.3.2 Auxiliary Power Supply Test
      3. 4.3.3 Current Open Loop Test
      4. 4.3.4 Overcurrent Protection Test
      5. 4.3.5 Motor Start-Up Sequence
      6. 4.3.6 Load Test
    4. 4.4 Migrate Firmware to a New Hardware Board
      1. 4.4.1 Configure the PWM, CMPSS, and ADC Modules
      2. 4.4.2 Motor and Control Parameters Tuning
  11. 5Design and Documentation Support
    1. 5.1 Design Files
      1. 5.1.1 Schematics
      2. 5.1.2 BOM
    2. 5.2 Tools
    3. 5.3 Documentation Support
    4. 5.4 Support Resources
    5. 5.5 Trademarks
  12. 6About the Author
  13. 7Revision History

3.9 Overcurrent Protection

This reference design implements overcurrent protection (OCP) with both external op amps and an internal comparator. Figure 3-8 shows the external op amp OCP, this circuit summarize three phases of current, then compares to a reference voltage (0.2V) to create an overcurrent fault signal. The other OCP is an internal comparator for a single shunt resistor current sensing. Internal op amp output can be connected directly to an internal comparator, to accomplish overcurrent protection. The designed external op amp OCP trigger point is 6A peak phase current, while the OCP trigger point for the internal comparator can be set by the internal reference.

TIDA-010250 External Overcurrent Protection CircuitFigure 3-8 External Overcurrent Protection Circuit