SNOSDE5A December   2021  – May 2022 LM74502 , LM74502H

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 Input Voltage
      2. 8.3.2 Charge Pump (VCAP)
      3. 8.3.3 Gate Driver (GATE, SRC)
        1. 8.3.3.1 Inrush Current Control
      4. 8.3.4 Enable (EN/UVLO)
      5. 8.3.5 Overvoltage Protection (OV)
    4. 8.4 Device Functional Modes
      1. 8.4.1 Shutdown Mode
      2. 8.4.2 Conduction Mode
  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 Design Considerations
        2. 9.2.2.2 MOSFET Selection
        3. 9.2.2.3 Overvoltage Protection
        4. 9.2.2.4 Charge Pump VCAP, Input and Output Capacitance
      3. 9.2.3 Application Curves
    3. 9.3 Input Surge Stopper Using LM74502, LM74502H
      1. 9.3.1 VS Capacitance, Resistor R1 and Zener Clamp (DZ)
      2. 9.3.2 Overvoltage Protection
      3. 9.3.3 MOSFET Selection
    4. 9.4 Fast Turn-On and Turn-Off High Side Switch Driver Using LM74502H
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Receiving Notification of Documentation Updates
    2. 12.2 Support Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

3 Description

The LM74502, LM74502H is a controller which operates in conjunction with an external back-to-back connected N-channel MOSFETs to realize a low loss reverse polarity protection and load disconnect solution. The device can also be configured to drive high side MOSFET as a load switch with overvoltage protection . The wide supply input range of 3.2 V to 65 V allows control of many popular DC bus voltages such as 12-V, 24-V and 48-V input systems. The device can withstand and protect the loads from negative supply voltages down to –65 V. The LM74502, LM74502H does not have reverse current blocking and is suitable for input reverse polarity protection only.

The LM74502 controller provides a charge pump gate drive for an external N-channel MOSFET. with the enable pin low, the controller is off and draws approximately 1 µA of current, thus offering low system current when put into sleep mode. LM74502 and LM74502H offers programmable overvoltage and undervoltage protection which cuts off the load from the input source in case of these fault events. The devices are available in a 2.9 mm × 1.6 mm 8-pin DDF package and are specified over a –40°C to +125°C temperature range.

Device Information(1)
PART NUMBERPACKAGEBODY SIZE (NOM)
LM74502SOT-23 (8)2.90 mm × 1.60 mm
LM74502H
(1) For all available packages, see the orderable addendum at the end of the data sheet.
LM74502 Typical Application Schematic
LM74502 as a Load Switch Controller with Overvoltage Protection