SNOU176B October   2020  – March 2022

PRODUCTION DATA  

  1.   Trademarks
  2. 1 General TI High Voltage Evaluation User Safety Guidelines
    1. 1.1 Safety and Precautions
  3. 2 Introduction
    1. 2.1 LMG342XEVM-04X Daughter Card
      1. 2.1.1 FAULT and OC
      2. 2.1.2 Power Pins
      3. 2.1.3 Bootstrap Mode
      4. 2.1.4 Heat Sink
    2. 2.2 Mother Boards
      1. 2.2.1 Bias Supply
      2. 2.2.2 PWM Input
      3. 2.2.3 Fault Protection
    3. 2.3 Typical Applications
    4. 2.4 Features
  4. 3  LMG342XEVM-04X Schematic
  5. 4 Mother Board Schematic
  6. 5 Recommended Footprint
  7. 6 Test Equipment
  8. 7 Test Procedure When Paired With LMG342X-BB-EVM
    1. 7.1 Setup
    2. 7.2 Start-Up and Operating Procedure
    3. 7.3 Test Results
    4. 7.4 Shutdown Procedure
    5. 7.5 Additional Operating Notes
  9. 8 Test Procedure When Paired With LMG34XX-BB-EVM
    1. 8.1 Setup
      1. 8.1.1 List of Test Points
      2. 8.1.2 List of Terminals
    2. 8.2 Start-Up and Operating Procedure
    3. 8.3 Shutdown Procedure
    4. 8.4 Additional Operation Notes
  10. 9 Bill of Materials
  11. 10Revision History

2.1.3 Bootstrap Mode

The LMG342XEVM-04X card can be modified to operate in bootstrap mode, where the 12-V bias voltage is used to power both LMG342XR0X0 devices. This mode can be achieved by the following modifications to the EVM:

  1. Remove R1.
  2. Place a 2-Ω resistor on R2.
  3. Place a 600-V SOD-123 diode on D1, such as UFM15PL-TP.
  4. Adjust Rdrv resistor for the low side to be above 70 kΩ, which corresponds to a slew rate below 60 V/ns for the low side. During starup, FAULT signal from the top GaN device is used to control Q1 on the bottom GaN device to operate it at lower slew rate. Once the bootstrap power supply is ready, the bottom GaN, U2 switch to normal operation which is higher slew rate.