TIDUEX5 October   2020

 

  1.   Description
  2.   Resources
  3.   Applications
  4.   Features
  5.   5
  6. 1System Description
    1. 1.1 Key System Specifications
  7. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
      1. 2.2.1 Ideal Diode Design Overview
      2. 2.2.2 Current Sensing Amplifier Design Overview
      3. 2.2.3 OR Gate Design Overview
      4. 2.2.4 MOSFET Selection
        1. 2.2.4.1 Blocking MOSFET
        2. 2.2.4.2 Hot-Swap MOSFET
      5. 2.2.5 TVS Input Diode Selection
      6. 2.2.6 Inrush Current
    3. 2.3 Highlighted Products
      1. 2.3.1 LM74810-Q1
      2. 2.3.2 INA302-Q1
  8. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Hardware Requirements
      1. 3.1.1 Getting Started
      2. 3.1.2 Testing and Results
        1. 3.1.2.1 Over-Voltage Protection Cut-Off Mode
        2. 3.1.2.2 Over-Voltage Protection Clamping-Mode
        3. 3.1.2.3 ISO7637-2 Pulse 1
        4. 3.1.2.4 Overcurrent Protection
        5. 3.1.2.5 Load Dump
        6. 3.1.2.6 Cold Crank, Warm Start, and Cold Start
          1. 3.1.2.6.1 Cold Crank
          2. 3.1.2.6.2 Warm Start
          3. 3.1.2.6.3 Cold Start
        7. 3.1.2.7 Standby Current
        8. 3.1.2.8 Currency Sense Accuracy
  9. 4Design and Documentation Support
    1. 4.1 Design Files
      1. 4.1.1 Schematics
      2. 4.1.2 BOM
    2. 4.2 Documentation Support
    3. 4.3 Support Resources
    4. 4.4 Trademarks

2.2.3 OR Gate Design Overview

SN74LVC1G32-Q2 is a 2-input positive OR gate designed for 1.65- to 5.5V VCC operation. It is designed to perform Boolean OR function on the ALERT1 and ALERT2 pins. The OR gate is tied to the enable pin of LM74810, allowing the device to turn off when both ALERT1 and ALERT2 are pulled low from detecting an overcurrent conditions from their comparators. The configuration allows flexibility by using both ALERT1 and ALERT2 comparator output pins which have independent overcurrent trigger levels as well as independent response times as shown in Current Sensing Amplifier Design Overview section. Comparator 2 can be set to trigger at a lower level relatively to comparator 1, allowing an MCU to read ALERT1 to serve as a sustained high current warning. Comparator 1 can be set to a higher trigger level, pulling low during an overcurrent condition.