SNVS465G October   2006  – September 2015 LM3404 , LM3404HV

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 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Controlled On-Time Overview
      2. 7.3.2 Average LED Current Accuracy
      3. 7.3.3 Maximum Output Voltage
      4. 7.3.4 Minimum Output Voltage
      5. 7.3.5 High Voltage Bias Regulator
      6. 7.3.6 Internal MOSFET and Driver
      7. 7.3.7 Fast Shutdown for PWM Dimming
      8. 7.3.8 Peak Current Limit
      9. 7.3.9 Overvoltage and Overcurrent Comparator
    4. 7.4 Device Functional Modes
      1. 7.4.1 Low-Power Shutdown
      2. 7.4.2 Thermal Shutdown
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Switching Frequency
      2. 8.1.2 LED Ripple Current
      3. 8.1.3 Buck Converters Without Output Capacitors
      4. 8.1.4 Buck Converters With Output Capacitors
      5. 8.1.5 Input Capacitors
      6. 8.1.6 Recirculating Diode
      7. 8.1.7 LED Current During DIM Mode
      8. 8.1.8 Transient Protection Considerations
        1. 8.1.8.1 CS Pin Protection
        2. 8.1.8.2 CS Pin Protection With OVP
        3. 8.1.8.3 VIN Pin Protection
        4. 8.1.8.4 General Comments Regarding Other Pins
    2. 8.2 Typical Applications
      1. 8.2.1 Design Example 1: LM3404
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 RON and tON
          2. 8.2.1.2.2 Output Inductor
          3. 8.2.1.2.3 Using an Output Capacitor
          4. 8.2.1.2.4 RSNS
          5. 8.2.1.2.5 Input Capacitor
          6. 8.2.1.2.6 Recirculating Diode
          7. 8.2.1.2.7 CB and CF
          8. 8.2.1.2.8 Efficiency
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Design Example 2: LM3404HV
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
          1. 8.2.2.2.1 RON and tON
          2. 8.2.2.2.2 Output Inductor
          3. 8.2.2.2.3 Using an Output Capacitor
          4. 8.2.2.2.4 RSNS
          5. 8.2.2.2.5 Input Capacitor
          6. 8.2.2.2.6 Recirculating Diode
          7. 8.2.2.2.7 CB and CF
          8. 8.2.2.2.8 Efficiency
        3. 8.2.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Compact Layout
      2. 10.1.2 Ground Plane and Shape Routing
      3. 10.1.3 Current Sensing
      4. 10.1.4 Remote LED Arrays
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
    2. 11.2 Related Links
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

1 Features

  • Integrated 1-A MOSFET
  • VIN Range 6 V to 42 V (LM3404)
  • VIN Range 6 V to 75 V (LM3404HV)
  • 1.2-A Output Current Overtemperature
  • Cycle-by-Cycle Current Limit
  • No Control Loop Compensation Required
  • Separate PWM Dimming and Low Power Shutdown
  • Supports All-Ceramic Output Capacitors and Capacitor-less Outputs
  • Thermal Shutdown Protection
  • SOIC-8 Package, SO PowerPAD™-8 Package

2 Applications

  • LED Drivers
  • Constant Current Sources
  • Automotive Lighting
  • General Illumination
  • Industrial Lighting

3 Description

The LM3404 and LM3404HV devices are monolithic switching regulators designed to deliver constant currents to high power LEDs. Ideal for automotive, industrial, and general lighting applications, these devices contain a high-side N-channel MOSFET switch with a current limit of
1.5-A (typical) for step-down (Buck) regulators. Hysteretic controlled on-time and an external resistor allow the converter output voltage to adjust as needed to deliver a constant current to series and series-parallel connected LED arrays of varying number and type. Some features are: LED dimming using pulse width modulation (PWM), broken or open LED protection, low-power shutdown, and thermal shutdown.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
LM3404, LM3404HV SOIC (8) 3.91 mm × 4.90 mm
SO PowerPAD (8) 3.90 mm × 4.89 mm
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Typical Application Diagram

LM3404 LM3404HV 20205401.gif