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

2.7 Test Points:

Table 2-1 lists the LM74721EVM board input and output connector functionality. Table 2-2 and Table 2-3 provide the test points description and the jumper functionality of the EVM respectively.

Table 2-1 Connectors: Input and Output
ConnectorDescription
J2Power input connector to the positive rail of the input power supply
J6Ground connection for the power supply
J3Power output connector to the positive side of the load
J1Power output connector to the positive side after the optional LC filter
J7Ground connection for the load
Table 2-2 Test Points Description
Test Point Name Description

TP1

 VIN Input power supply to the EVM

TP2

 VOUT Output from the EVM

TP3

 VIN_MON Input monitoring for battery inputs

TP6

 GATE Output of Ideal Diode MOSFET Gate Control

TP7

 PD Output of Hot-Swap MOSFET Gate Control

TP8

CAP1

Internal Boost Regulator output

TP9

C

Cathode pin

TP4, TP5

 PGND Test Point for EVM Ground
Table 2-3 Jumpers and LED Description
Jumpers Description
J5 EN/UVLO control
  • 1-2 enables by connecting to common drain point
  • 2-3 disables by connecting to GND
J7 Enables LED indication for output