SLUUCR5A december   2022  – june 2023 LM74900-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
    1. 1.1 EVM Features
    2. 1.2 EVM Applications
  5. 2Description
  6. 3Schematic
  7. 4General Configurations
    1. 4.1 Physical Access
    2. 4.2 Test Equipment and Setup
      1. 4.2.1 Power Supplies
      2. 4.2.2 Meters
      3. 4.2.3 Oscilloscope
      4. 4.2.4 Loads
  8. 5Test Setup and Procedures
    1. 5.1 Power-Up and Power-Down With EN Control
    2. 5.2 Input Overvoltage Test
    3. 5.3 Overcurrent Protection Test
    4. 5.4 Output Hot-Short Test
  9. 6EVAL Board Assembly Drawings
    1. 6.1 PCB Drawings
  10. 7Bill of Materials (BOM)
  11. 8Revision History

5.3 Overcurrent Protection Test

Use the following instructions to perform the overcurrent test on the LM74900Q1EVM.

  1. Set the input supply voltage VIN to 12 V and current limit of 10 A.
  2. Turn ON the power supply and observe start-up of output voltage, HGATE, and DGATE.
  3. By default the EVM is configured for 5-A overcurrent protection.
  4. Apply 4-A load at the output with rheostat or electronic load and gradually increase the load current to 6 A.
  5. Observe the overload behavior of LM74900-Q1.

Figure 5-7 and Figure 5-8 show test waveforms for an overcurrent fault.

GUID-20221128-SS0I-3V6M-BZCV-P629Q81R1DZS-low.png Figure 5-7 Overcurrent Response of LM74900-Q1 for a Load Step From 4 A to 6 A With 5-A Overcurrent Protection Setting
GUID-20221128-SS0I-J0KB-SWMH-PSK2H4VCGQ2S-low.png Figure 5-8 Auto-Retry Response of LM74900-Q1 for an Overcurrent Fault