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

2.2 Enable Control (J4 and J11):

Enable control is usually used by external MCU or controller to turn off LM7472x-Q1 and cut off the power path. Setting 1-2 on J4 (channel 1) and J11 (channel 2) enables the controller and 2-3 disables the controller. TI recommends to connect EN to external MCU or to test point 1-2 for uninterrupted performance during negative transient tests.