SLVSFD0 September   2019 LM74202-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Schematic
      2.      ISO16750-2 Load Dump Pulse 5b Performance at 12 V
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 6 Specifications
    1. 6.1      Absolute Maximum Ratings
    2. 6.2      ESD Ratings
    3. 6.3      Recommended Operating Conditions
    4. Table 1. Thermal Information
    5. 6.4      Electrical Characteristics
    6. 6.5      Timing Requirements
    7. 6.6      Typical Characteristics
  7. 7 Parameter Measurement Information
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Undervoltage Lockout (UVLO)
      2. 8.3.2 Overvoltage Protection (OVP)
      3. 8.3.3 Reverse Battery Protection
      4. 8.3.4 Hot Plug-In and In-Rush Current Control
      5. 8.3.5 Overload and Short Circuit Protection
        1. 8.3.5.1 Overload Protection
          1. 8.3.5.1.1 Active Current Limiting
          2. 8.3.5.1.2 Electronic Circuit Breaker with Overload Timeout, MODE = OPEN
        2. 8.3.5.2 Short Circuit Protection
          1. 8.3.5.2.1 Start-Up With Short-Circuit On Output
        3. 8.3.5.3 FAULT Response
          1. 8.3.5.3.1 Look Ahead Overload Current Fault Indicator
        4. 8.3.5.4 Current Monitoring
        5. 8.3.5.5 IN, OUT, RTN and GND Pins
        6. 8.3.5.6 Thermal Shutdown
        7. 8.3.5.7 Low Current Shutdown Control (SHDN)
    4. 8.4 Device Functional Modes
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Step by Step Design Procedure
        2. 9.2.2.2 Setting Undervoltage Lockout and Overvoltage Set Point for Operating Voltage Range
        3. 9.2.2.3 Programming the Current-Limit Threshold—R(ILIM) Selection
        4. 9.2.2.4 Programming Current Monitoring Resistor—RIMON
        5. 9.2.2.5 Limiting the Inrush Current
          1. 9.2.2.5.1 Selection of Input TVS for Transient Protection
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
    1. 10.1 Transient Protection
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 Receiving Notification of Documentation Updates
    3. 12.3 Community Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

9.2.2.5.1 Selection of Input TVS for Transient Protection

To protect the device and the load from input transients exceeding the absolute maximum ratings of the device, a TVS diode is required at input of the device. To meet the requirements of protection for ISO 16750 pulse 5b and ISO 7637 pulse 1 as per Table 5, SMBJ28CA is selected for protection from transients.

Table 5. Input TVS Selection for Transients

Parameter ISO 16750 Pulse 5b ISO 7637 Pulse 1 and Reverse Battery
Maximum Transient Voltage of Pulse (VT) 35 V -150V A bidirectional TVS is required to protect from positive and negative transients
Pulse Current through TVS (IPulse) (VT - VC)/(Ri) (VT - VC)/(Ri) Ri = Source impedance.
For ISO 16750 Pulse 5b; Ri = 0.5 Ω
For ISO 7637 Pulse 1;Ri = 10 Ω
Clamping voltage of TVS (VC) at Pulse current IPulse < 55 V > –(55 - VOUT-Max) V To keep input voltage below absolute maximum rating of the device. See Equation 13 for VC
Breakdown voltage of TVS (VBR) > 32V > 14V To operate with maximum operating input voltage and to protect from maximum reverse battery voltage
Equation 13. VC = VBR + IPulse × [VClamp-max - VBR]/[IPP - IT]

where

  • VC is the clamping voltage of TVS at IPulse current through it.
  • VBR is break down voltage of TVS with IT test current through it.
  • VClamp-max is maximum clamping voltage of TVS at peak pulse current IPP
  • VBR, IT, VClamp-max and IPP are the specifications of the TVS diode.