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

8.4 Device Functional Modes

The device responds differently to overload and short circuit conditions. The operational differences are explained in Table 3.

Table 3. Device Operational Differences Under Different MODE Configurations

Mode Pin Configuration Mode Connected To RTN (Current Limit With Auto-Retry) A 402-KΩ Resistor Connected Between Mode And RTN Pins (Current Limit With Latchoff) Mode Pin = Open
Start-up Inrush current controlled by dVdT
Inrush limited to I(OL) level as set by R(ILIM) Inrush limited to I(OL) level as set by R(ILIM) Inrush limited to I(OL) level as set by R(ILIM)
Fault timer runs when current is limited to I(OL)
Fault timer expires after tCB(dly) causing the FETs to turnoff
If TJ > T(TSD), device turns off If TJ > T(TSD), device turns off Device turns off if TJ > T(TSD) before timer expires
Overcurrent response Current is limited to I(OL) level as set by R(ILIM) Current is limited to I(OL) level as set by R(ILIM) Current is allowed through the device if I(LOAD) < I(FASTTRIP)
Power dissipation increases as V(IN) – V(OUT) increases Power dissipation increases as V(IN) – V(OUT) increases Fault timer runs when the current increases above I(OL)
Fault timer expires after tCB(dly) causing the FETs to turnoff
Device turns off when TJ > T(TSD) Device turns off when TJ > T(TSD) Device turns off if TJ > T(TSD) before timer expires
Device attempts restart 540 ms after TJ < [T(TSD) – 10°C] Device remains off Device attempts restart 540 ms after TJ < [T(TSD) – 10°C].
Short-circuit response Fast turnoff when I(LOAD) > I(FASTRIP)
Quick restart and current limited to I(OL), follows standard start-up