SNOAA69 April   2021 LM36922 , LM36923 , LM3697

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 LM3697 Key Specifications
    2. 1.2 LM3697 Simplified Block Diagram
  3. 2How to map Exponential Data to the Linear Dimming Lookup Table
    1. 2.1 Why use Exponential Data for Dimming?
    2. 2.2 Design Sample: Map Exponential Data to Linear Brightness Dimming Lookup Table
  4. 3Key LM369xx Design Tips
    1. 3.1 Simplified Schematic
    2. 3.2 How to Choose Key Components: Inductor and Capacitor, Schottky Diode D1
  5. 4LM369xx PCB Layout Tips
  6. 5References

3.1 Simplified Schematic

GUID-BD4FA327-A264-4955-924D-39B70EED94B6-low.gifFigure 3-1 LM3697 Typical Schematic
  • COUT is output filter capacitor, the maximum resistant voltage has to be higher than VOUT.
  • Schottky Diode D1 is used to rectify and generate high voltage to drive the LED string, the maximum reversed voltage has to be higher than VOUT.
  • Power inductor L is used to store power energy to drive the LED string.
  • For the unused channel pin, float it.