SLVUBU4 March   2021

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 Features
    2. 1.2 Applications
  3. 2Description
    1. 2.1 Input Power and Load (J1/J3 and J2/J4):
    2. 2.2 Enable Control (J5):
    3. 2.3 Over Voltage Protection (J6):
    4. 2.4 Two Back-Back Connected MOSFETs (Q1/Q3 and Q2):
    5. 2.5 Output Slew Rate Control (R2 and C4):
    6. 2.6 Output Schottky Diode (D3) and LED Indication:
    7. 2.7 TVS Selection for 200-V Unsuppressed Load Dump 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. 5.3 200-V Unsuppressed Load Dump Protection
    4. 5.4 ISO 7637-2 Pulse 1 –600 V 50 Ω
  7. 6Board Layout and Bill of Materials
    1. 6.1 Board Layout
    2. 6.2 Bill of Materials
  8.   Revision History

2.7 TVS Selection for 200-V Unsuppressed Load Dump Protection:

Two TVS diodes D1 and D2 are required at the input. The breakdown voltage of two TVS in the positive side is higher than the maximum system voltage, 200 V. On the negative side, diode D3 is used to clamp ISO 7637-2 pulse 1. SMBJ150A for D2 and SMBJ33CA for D1 are recommended.