SNOSDD9 December   2022 LM7481

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 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
  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 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 Overvoltage Protection and Battery Voltage sensing (VSNS, SW, OV)
      4. 8.3.4 Low Iq Shutdown and Undervoltage Lockout (EN/UVLO)
    4. 8.4 Device Functional Modes
    5. 8.5 Application Examples
      1. 8.5.1 Redundant Supply OR-ing With Inrush Current Limiting, Overvoltage Protection and ON/OFF Control
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical 12-V Reverse Battery Protection Application
      1. 9.2.1 Design Requirements for 12-V Battery Protection
      2. 9.2.2 Automotive Reverse Battery Protection
      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 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 Do's and Don'ts
    4. 9.4 Power Supply Recommendations
      1. 9.4.1 Transient Protection
      2. 9.4.2 TVS Selection for 12-V Battery Systems
      3. 9.4.3 TVS Selection for 24-V Battery Systems
    5. 9.5 Layout
      1. 9.5.1 Layout Guidelines
      2. 9.5.2 Layout Example
  10. 10Device and Documentation Support
    1. 10.1 Receiving Notification of Documentation Updates
    2. 10.2 Support Resources
    3. 10.3 Trademarks
    4. 10.4 Electrostatic Discharge Caution
    5. 10.5 Glossary
  11. 11Mechanical, Packaging, and Orderable Information

Package Options

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

8.3.3 Overvoltage Protection and Battery Voltage sensing (VSNS, SW, OV)

Connect a resistor ladder as shown in Figure 8-4 for Overvoltage threshold programming.

Figure 8-4 Programming Overvoltage Threshold and Battery Sensing

A disconnect switch is integrated between VSNS and SW pins. This switch is turned OFF when EN/UVLO pin is pulled low. This helps to reduce the leakage current through the resistor divider network during system shutdown state (IGN_OFF state).