SNOSDE6C December   2022  – August 2025 LM74900-Q1 , LM74910-Q1 , LM74910H-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Switching Characteristics
    7. 6.7 Typical Characteristics
  8. 7 Parameter Measurement Information
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Charge Pump
      2. 8.3.2 Dual Gate Control (DGATE, HGATE)
        1. 8.3.2.1 Reverse Battery Protection (A, C, DGATE)
        2. 8.3.2.2 Load Disconnect Switch Control (HGATE, OUT)
      3. 8.3.3 Overcurrent Protection (CS+, CS-, ILIM, IMON, TMR)
        1. 8.3.3.1 Pulse Overload Protection, Circuit Breaker
        2. 8.3.3.2 Overcurrent Protection With Latch-Off
        3. 8.3.3.3 Short Circuit Protection (ISCP)
        4. 8.3.3.4 Analog Current Monitor Output (IMON)
      4. 8.3.4 Undervoltage Protection, Overvoltage Protection, and Battery Voltage Sensing (UVLO, OV, SW)
    4. 8.4 Device Functional Modes
      1. 8.4.1 Ultra Low IQ Shutdown (EN)
      2. 8.4.2 Low IQ SLEEP Mode (SLEEP)
  10. 9 Applications and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical 12V Reverse Battery Protection Application
      1. 9.2.1 Design Requirements for 12V Battery Protection
      2. 9.2.2 Automotive Reverse Battery Protection
        1. 9.2.2.1 Input Transient Protection: ISO 7637-2 Pulse 1
        2. 9.2.2.2 AC Super Imposed Input Rectification: ISO 16750-2 and LV124 E-06
        3. 9.2.2.3 Input Micro-Short Protection: LV124 E-10
      3. 9.2.3 Detailed Design Procedure
        1. 9.2.3.1 Design Considerations
        2. 9.2.3.2 Charge Pump Capacitance VCAP
        3. 9.2.3.3 Input and Output Capacitance
        4. 9.2.3.4 Hold-Up Capacitance
        5. 9.2.3.5 Selection of Current Sense Resistor, RSNS
        6. 9.2.3.6 Selection of Scaling Resistor (RSET) and Short-Circuit Protection Setting Resistor (RSCP)
        7. 9.2.3.7 Overcurrent Limit (ILIM), Circuit Breaker Timer (TMR), and Current Monitoring Output (IMON) Selection
        8. 9.2.3.8 Overvoltage Protection and Battery Monitor
      4. 9.2.4 MOSFET Selection: Blocking MOSFET Q1
      5. 9.2.5 MOSFET Selection: Hot-Swap MOSFET Q2
      6. 9.2.6 TVS Selection
      7. 9.2.7 Application Curves
    3. 9.3 Addressing Automotive Input Reverse Battery Protection Topologies With LM749x0-Q1
    4. 9.4 Power Supply Recommendations
      1. 9.4.1 Transient Protection
      2. 9.4.2 TVS Selection for 12V Battery Systems
    5. 9.5 Layout
      1. 9.5.1 Layout Guidelines
      2. 9.5.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Third-Party Products Disclaimer
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • RGE|24
Thermal pad, mechanical data (Package|Pins)
Orderable Information

9.2.3.5 Selection of Current Sense Resistor, RSNS

The LM749x0-Q1 has an integrated short circuit detection comparator with default sense threshold of 20mV. For this application, short circuit limit is set to 20A. The sense resistor value based on short circuit comparator can be calculated by Equation 11.

Equation 9. LM74900-Q1 LM74910-Q1 LM74910H-Q1

Select a 1mΩ resistor with 1% tolerance to set short circuit protection limit of 20A.