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

2.8 Test Points:

Table 2-1 lists the LM7472EVM board input and output connector functionality. Table 2-2 and Table 2-3 describe the test points description and the jumper functionality of the EVM respectively.

Table 2-1 Connectors: Input and Output

Channel

ConnectorDescription

1

J1Power input connector to the positive rail of the input power supply
J5Ground connection for the power supply
J2Power output connector to the positive side of the load
J6Ground connection for the load

2

J8Power input connector to the positive rail of the input power supply
J12Ground connection for the power supply
J9Power output connector to the positive side of the load
J7Power output connector to the positive side after the optional LC filter at output
J13Ground connection for the load
Table 2-2 Test Points Description

Test Point

 Name Description

TP1

 VIN1 Input power supply to the EVM - channel 1
TP2 VOUT1 Output from the EVM - channel 1
TP3 VIN_MON1 Input monitoring for battery inputs - channel 1
TP6 GATE1 Output of Ideal Diode MOSFET Gate Control - channel 1
TP7

PD1

 Output of Hot-Swap MOSFET Gate Control - channel 1
TP8

CAP1

Internal Boost Regulator output - channel 1
TP9

C1

Cathode pin - channel 1
TP10 VIN2 Input power supply to the EVM - channel 2
TP11 VOUT2 Output from the EVM - channel 2
TP12 VIN_MON2 Input monitoring for battery inputs - channel 2
TP15 GATE2 Output of Ideal Diode MOSFET Gate Control - channel 2
TP16 PD2 Output of Hot-Swap MOSFET Gate Control - channel 2
TP17 CAP2 Internal Boost Regulator output - channel 2

TP18

C2

 Cathode pin - channel 2
TP4, TP5, TP13, TP14 PGND Test Point for EVM Ground
Table 2-3 Jumpers and LED Description
JumpersDescription
J4EN/UVLO control channel 1
  • 1-2 enables by connecting to common drain point
  • 2-3 disables by connecting to GND
J3Enables LED indication for output - channel 1
J11EN/UVLO control channel 2
  • 1-2 enables by connecting to common drain point
  • 2-3 disables by connecting to GND
J10Enables LED indication for output - channel 2