TIDUF68 February   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 LMG2100
      2. 2.3.2 INA241A
      3. 2.3.3 LMR38010
  9. 3System Design Theory
    1. 3.1 Three-Phase GaN Inverter Power Stage
      1. 3.1.1 LMG2100 GaN Half-Bridge Power Stage
    2. 3.2 Inline Shunt Precision-Phase Current Sensing With INA241A
    3. 3.3 Phase Voltage and DC Input Voltage Sensing
    4. 3.4 Power-Stage PCB Temperature Monitor
    5. 3.5 Power Management
      1. 3.5.1 48V to 5V DC/DC Converter
      2. 3.5.2 5V to 3.3V Rail
    6. 3.6 Interface to Host MCU
  10. 4Hardware, Software, Testing Requirements, and Test Results
    1. 4.1 Hardware Requirements
      1. 4.1.1 TIDA-010936 PCB Overview
      2. 4.1.2 TIDA-010936 Jumper Settings
      3. 4.1.3 Interface to C2000™ MCU LaunchPad™ Development Kit
    2. 4.2 Software Requirements
    3. 4.3 Test Setup
    4. 4.4 Test Results
      1. 4.4.1 Power Management and System Power Up and Power Down
    5. 4.5 GaN Inverter Half-Bridge Module Switch Node Voltage
      1. 4.5.1 Switch Node Voltage Transient Response at 48V DC Bus
        1. 4.5.1.1 Output Current at ±1A
        2. 4.5.1.2 Output Current at ±10A
      2. 4.5.2 Impact of PWM Frequency to DC-Bus Voltage Ripple
      3. 4.5.3 Efficiency Measurements
      4. 4.5.4 Thermal Analysis
      5. 4.5.5 No Load Loss Test (COSS Losses)
  11. 5Design and Documentation Support
    1. 5.1 Design Files {Required Topic}
      1. 5.1.1 Schematics
      2. 5.1.2 BOM
      3. 5.1.3 PCB Layout Recommendations
        1. 5.1.3.1 Layout Prints
      4. 5.1.4 Altium Project
      5. 5.1.5 Gerber Files
      6. 5.1.6 Assembly Drawings
    2. 5.2 Tools and Software
    3. 5.3 Documentation Support
    4. 5.4 Support Resources
    5. 5.5 Trademarks
  12. 6About the Author
  13. 7Recognition

2.3.2 INA241A

The INA241A is an ultra-precise, bidirectional current sense amplifier than can measure voltage drops across shunt resistors over a wide common-mode range from –5V to 110V, independent of the supply voltage.


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Figure 2-3 INA241A Functional Block Diagram
Table 2-2 INA241A Features and Benefits
FEATUREBENEFIT
Fast-transient common-mode voltage input filtering (Enhanced PWM Rejection) and high AC common-mode rejection ratio (CMRR): 104dB at 100kHz and 166dB DC CMRREnables non-isolated shunt-based precision phase current measurement with three-phase inverters at high switching frequency of 40kHz and above.
Wide common-mode input voltage range: –5V to 110VProvides sufficient headroom for transient overvoltage and undervoltage in three-phase inverters with 48V to 80V DC link voltage.
Low offset voltage (VOS = ±10µV) and low gain error (0.01%)Low offset and gain error enables accurate current sensing without calibration.
Low offset voltage drift (0.25µV / °C) and gain error drift (1ppm / °C)Ultra-low offset and gain error drift allows high accurate current sensing over entire temperature range without temperature-dependent calibration.
1.1MHz signal bandwidthHigh signal bandwidth supports low latency phase current measurement of high-speed motors as well as low latency detection of high-current transients such as during a short-circuit event.
Integrated output mid-point voltage reference voltage dividerAllows using an external ADC reference to set the INA241 mid-point voltage to half of the ADC reference voltage. This eliminates any offset generated by the ADC reference voltage drift.