SNVS967A August   2014  – November 2014 LM3643

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Simplified Schematic
  5. 5 Revision History
  6. 6 Device Comparison Table
  7. 7 Pin Configuration and Functions
  8. 8 Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 Handling Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Electrical Characteristics
    6. 8.6 Timing Requirements
    7. 8.7 Switching Characteristics
    8. 8.8 Typical Characteristics
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Flash Mode
      2. 9.3.2 Torch Mode
      3. 9.3.3 IR Mode
    4. 9.4 Device Functioning Modes
      1. 9.4.1 Start-Up (Enabling The Device)
      2. 9.4.2 Pass Mode
      3. 9.4.3 Power Amplifier Synchronization (TX)
      4. 9.4.4 Input Voltage Flash Monitor (IVFM)
      5. 9.4.5 Fault/Protections
        1. 9.4.5.1 Fault Operation
        2. 9.4.5.2 Flash Time-Out
        3. 9.4.5.3 Overvoltage Protection (OVP)
        4. 9.4.5.4 Current Limit
        5. 9.4.5.5 NTC Thermistor Input (Torch/Temp)
        6. 9.4.5.6 Undervoltage Lockout (UVLO)
        7. 9.4.5.7 Thermal Shutdown (TSD)
        8. 9.4.5.8 LED and/or VOUT Short Fault
    5. 9.5 Programming
      1. 9.5.1 Control Truth Table
      2. 9.5.2 I2C-Compatible Interface
        1. 9.5.2.1 Data Validity
        2. 9.5.2.2 Start and Stop Conditions
        3. 9.5.2.3 Transferring Data
        4. 9.5.2.4 I2C-Compatible Chip Address
    6. 9.6 Register Descriptions
      1. 9.6.1  Enable Register (0x01)
      2. 9.6.2  IVFM Register (0x02)
      3. 9.6.3  LED1 Flash Brightness Register (0x03)
      4. 9.6.4  LED2 Flash Brightness Register (0x04)
      5. 9.6.5  LED1 Torch Brightness Register (0x05)
      6. 9.6.6  LED2 Torch Brightness Register (0x06)
      7. 9.6.7  Boost Configuration Register (0x07)
      8. 9.6.8  Timing Configuration Register (0x08)
      9. 9.6.9  TEMP Register (0x09)
      10. 9.6.10 Flags1 Register (0x0A)
      11. 9.6.11 Flags2 Register (0x0B)
      12. 9.6.12 Device ID Register (0x0C)
      13. 9.6.13 Last Flash Register (0x0D)
  10. 10Applications and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 Output Capacitor Selection
        2. 10.2.2.2 Input Capacitor Selection
        3. 10.2.2.3 Inductor Selection
      3. 10.2.3 Application Curves
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Device Support
      1. 13.1.1 Third-Party Products Disclaimer
    2. 13.2 Related Documentation
      1. 13.2.1 Related Links
    3. 13.3 Trademarks
    4. 13.4 Electrostatic Discharge Caution
    5. 13.5 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

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

11 Power Supply Recommendations

The LM3643 is designed to operate from an input voltage supply range between 2.5 V and 5.5 V. This input supply must be well regulated and capable to supply the required input current. If the input supply is located far from the LM3643 additional bulk capacitance may be required in addition to the ceramic bypass capacitors.