TIDUF28 November   2023

 

  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 Highlighted Products
      1. 2.2.1 LMG3422R030
      2. 2.2.2 ISO7741
      3. 2.2.3 AMC1306M05
      4. 2.2.4 AMC1035
      5. 2.2.5 TPSM560R6H
      6. 2.2.6 TPSM82903
  9. 3System Design Theory
    1. 3.1 Power Switches
      1. 3.1.1 GaN-FET Selection Criterion
      2. 3.1.2 HVBUS Decoupling and 12-V Bootstrap Supply
      3. 3.1.3 GaN_FET Turn-on Slew Rate Configuration
      4. 3.1.4 PWM Input Filter and Dead-Time Calculation
      5. 3.1.5 Signal Level Shifting
      6. 3.1.6 LMG3422R030 Fault Reporting
      7. 3.1.7 LMG3422R030 Temperature Monitoring
    2. 3.2 Phase Current Sensing
      1. 3.2.1 Shunt
      2. 3.2.2 AMC1306M05 Analog Input-Filter
      3. 3.2.3 AMC1306M05 Digital Interface
      4. 3.2.4 AMC1306M05 Supply
    3. 3.3 DC-Link (HV_BUS) Voltage Sensing
    4. 3.4 Phase Voltage Sensing
    5. 3.5 Control Supply
    6. 3.6 MCU Interface
  10. 4Hardware, Software, Testing Requirements, and Test Results
    1. 4.1 Hardware Requirements
      1. 4.1.1 PCB
      2. 4.1.2 MCU Interface
    2. 4.2 Software Requirements
    3. 4.3 Test Setup
      1. 4.3.1 Precautions
      2. 4.3.2 Test Procedure
    4. 4.4 Test Results
      1. 4.4.1 24-V Input Control Supply
      2. 4.4.2 Propagation Delay PWM to Phase Voltage Switch Node
      3. 4.4.3 Switch Node Transient at 320-VDC Bus Voltage
      4. 4.4.4 Phase Voltage Linearity and Distortion at 320 VDC and 16-kHz PWM
      5. 4.4.5 Inverter Efficiency and Thermal Characteristic
        1. 4.4.5.1 Efficiency Measurements
        2. 4.4.5.2 Thermal Analysis and SOA Without Heat Sink at 320 VDC and 16-kHz PWM
  11. 5Design and Documentation Support
    1. 5.1 Design Files
      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

Features

  • High-efficiency, 3-phase GaN-FET power stage with 99.4% peak efficiency at 16-kHz PWM at 320-V DC-link voltage helps reduce the heat sink size
  • LMG3422R030 600-V, 30-mΩ GaN FETs with integrated driver, overcurrent and overtemperature protection, and temperature reporting
  • LMG3422R030 integrated protection increases reliability and reduces system cost, on-chip temperature sensor enables precise monitoring of the die temperature to maximize safe operation area (SOA)
  • Zero reverse recovery losses reduce switch node oscillations, and fast switching capability dV/dt (30 V/ns, configurable from 20 V/ns to 100 V/ns) with low dead time of 120-ns minimize phase voltage distortions
  • Precision phase current sensing with ±50-A linear range using 1-mΩ shunt and isolated delta-sigma modulator AMC1306M05
  • Interface with 3.3 V I/O enables easy evaluation of TI GaN technology for motor drives with C2000, Sitara, or other MCUs