SNOU187 September   2021

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 Features
    2. 1.2 Applications
  3. 2Description
    1. 2.1 Input Power and Load (J2, J6 and J3, J7):
    2. 2.2 Enable Control (J5):
    3. 2.3 Two Back-to-Back Connected MOSFETs (Q1 and Q2):
    4. 2.4 Output Slew Rate Control (R5 and C5):
    5. 2.5 Output Schottky Diode (D3) and LED Indication:
    6. 2.6 TVS Selection for 12-V Battery Protection:
    7. 2.7 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

1 Introduction

TI's LM74721 Evaluation Module LM74721EVM helps designers evaluate the operation and performance of the LM74721-Q1 ideal diode controller with switched output. This evaluation module demonstrates how
LM74721-Q1 controls two N-channel power MOSFETs with ideal diode MOSFET connected first followed by second MOSFET for switched output and power path cut-off. The device can withstand and protect the loads from negative supply voltages down to –33-V DC. An integrated ideal diode controller (GATE) drives the first MOSFET to replace a Schottky diode for reverse input protection and output voltage holdup. Integrated VDS clamp feature enables input TVS less system designs for automotive ISO7637 pulse suppression. A strong boost regulator with fast turn ON/OFF comparators ensures robust and efficient MOSFET switching performance during automotive testing such as ISO16750 or LV124 where an ECU is subjected to input short interruptions and AC superimpose input signals.