SNVS532D October   2007  – August 2020 LM5067

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison
  6. 6 Pin Configuration and Functions
    1.     Pin Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Switching Characteristics
    7. 7.7 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Power Up Sequence
      2. 8.3.2 Gate Control
      3. 8.3.3 Current Limit
      4. 8.3.4 Circuit Breaker
      5. 8.3.5 Power Limit
      6. 8.3.6 Fault Timer and Restart
      7. 8.3.7 Undervoltage Lock-Out (UVLO)
      8. 8.3.8 Overvoltage Lock-Out (OVLO)
      9. 8.3.9 Power Good Pin
    4. 8.4 Device Functional Modes
      1. 8.4.1 Shutdown / Enable Control
  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  RIN, CIN
        2. 9.2.2.2  Current Limit, RS
        3. 9.2.2.3  Power Limit Threshold
        4. 9.2.2.4  Turn-On Time
          1. 9.2.2.4.1 Turn-on With Current Limit Only
          2. 9.2.2.4.2 Turn-on With Power Limit and Current Limit
        5. 9.2.2.5  MOSFET Selection
        6. 9.2.2.6  Timer Capacitor, CT
          1. 9.2.2.6.1 Insertion Delay
          2. 9.2.2.6.2 Fault Timeout Period
          3. 9.2.2.6.3 Restart Timing
        7. 9.2.2.7  UVLO, OVLO
          1. 9.2.2.7.1 Option A:
          2. 9.2.2.7.2 Option B:
          3. 9.2.2.7.3 Option C:
          4. 9.2.2.7.4 Option D:
        8. 9.2.2.8  Thermal Considerations
        9. 9.2.2.9  System Considerations
          1. 9.2.2.9.1 System Considerations During Surge Events
        10. 9.2.2.10 Power Good Pin
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
    1. 10.1 Operating Voltage
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Trademarks
    2. 12.2 Electrostatic Discharge Caution
    3. 12.3 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

8.3.5 Power Limit

An important feature of the LM5067 is the MOSFET power limiting. The Power Limit function can be used to maintain the maximum power dissipation of MOSFET Q1 within the device SOA rating. The LM5067 determines the power dissipation in Q1 by monitoring its drain-source voltage (OUT to SENSE), and the drain current through the sense resistor (SENSE to VEE). The product of the current and voltage is compared to the power limit threshold programmed by the resistor at the PWR pin. If the power dissipation reaches the limiting threshold, the GATE voltage is modulated to reduce the current in Q1, and the fault timer is active as described in the Fault Timer and Restart section.