SNOSDF8 December   2024 LM74680

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Switching Characteristics
    7. 5.7 Typical Characteristics
  7. 6 Parameter Measurement Information
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Input and Output Voltage
      2. 7.3.2 Charge Pump
      3. 7.3.3 Gate Drivers
      4. 7.3.4 Enable
    4. 7.4 Device Functional Modes
      1. 7.4.1 Conduction Mode
        1. 7.4.1.1 Regulated Conduction Mode
        2. 7.4.1.2 Full Conduction Mode
      2. 7.4.2 Reverse Current Protection Mode
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Design Considerations
        2. 8.2.2.2 MOSFET Selection
        3. 8.2.2.3 Output Capacitance
      3. 8.2.3 Application Curves
    3. 8.3 Power Supply Recommendations
      1. 8.3.1 Transient Protection
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Receiving Notification of Documentation Updates
    2. 9.2 Support Resources
    3. 9.3 Trademarks
    4. 9.4 Electrostatic Discharge Caution
    5. 9.5 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

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

8.1 Application Information

The LM74680 drives four external N-channel MOSFETs in a diode bridge configuration, making it ideal for rectifying an AC power supplies or polarity-agnostic DC power supplies. By replacing traditional diodes with MOSFETs, the device minimizes conduction losses, resulting in improved thermal performance and increased overall system efficiency. This makes it suitable for applications such as video door bell, industrial automation, HVAC systems, and other AC-powered equipment where low power loss and high reliability are critical. The schematic for a 24V AC input application is shown in Figure 8-1 where the LM74680 is driving the high side MOSFETs Q1, Q2 and low side MOSFETs Q3, Q4 in diode bridge configuration.