SNOU186 September   2021 LM74720-Q1 , LM74722-Q1

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 Features
    2. 1.2 Applications
  3. 2Description
    1. 2.1 Input Power and Load (J1/J5 and J2/J6, J8/J12 and J9/J13):
    2. 2.2 Enable Control (J4 and J11):
    3. 2.3 Two Back-to-Back Connected MOSFETs (Q1/Q3-Q2/Q4 and M1/M3-M2/M4):
    4. 2.4 Output Slew Rate Control (R3 and C4, R10 and C13):
    5. 2.5 Output Schottky Diode (D3, D8) and LED Indication (D4, D10) :
    6. 2.6 TVS Selection for 12-V Battery Protection:
    7. 2.7 TVS Selection for 24-V Battery Protection:
    8. 2.8 Test Points:
  4. 3Schematic
  5. 4Test Equipment Requirements
    1. 4.1 Power Supplies
    2. 4.2 Meters
    3. 4.3 Oscilloscope
    4. 4.4 Loads
  6. 5Test Setup and Results
    1. 5.1 Initial Setup
    2. 5.2 Power Up
    3. 5.3 Enable Control
    4. 5.4 Hot-Plug and Disable using EN
    5. 5.5 Inrush Current Control
    6. 5.6 Load Response
  7. 6Board Layout and Bill of Materials
    1. 6.1 Board Layout
    2. 6.2 Bill of Materials

TVS Selection for 12-V Battery Protection:

TVS D2 (channel 1) and D7 (channel 2), SMBJ36CA is a bidirectional 600-W TVS that protects the LM7472x-Q1 and MOSFETs from automotive ISO transients tests on a 12-V battery. For detailed information on TVS selection, refer to the data sheets for LM74720-Q1 and LM74722-Q1.