SNVU822 May   2022

 

  1.   Trademarks
  2. 1Introduction
  3. 2Warnings and Cautions
  4. 3Description
    1. 3.1 Typical Applications
    2. 3.2 Features
    3. 3.3 Connector and Test Point Description
    4. 3.4 Electrical Performance Specifications
  5. 4Test Setup
    1. 4.1 Input Supplies and LED Load Connections
    2. 4.2 Analog Duty Cycle Control Using APWM
    3. 4.3 Analog Dimming Using IADJ
    4. 4.4 PWM Dimming Using nExt_PWM Test Points
    5. 4.5 Switching Frequency Set Point Using RON
  6. 5Performance Data and Typical Characteristic Curves
    1. 5.1 Efficiency
    2. 5.2 Analog Dimming
    3. 5.3 PWM Dimming
    4. 5.4 PWM Dimming Waveforms
  7. 6Schematic
  8. 7TPS92643EVM-204 PCB Layout
  9. 8Bill of Materials

4.5 Switching Frequency Set Point Using RON

The TPS92643EVM-204 is by default setup for a switching frequency of 440 kHz. If a switching frequency between 100-kHz and 2.1-MHz operation is desired, then both the inductors (L1 ) and RON (R5) must be changed. See TPS92643-Q1 Automotive 3-A Synchronous Buck LED Driver data sheet for more details for the design calculations.

Figure 4-9 Switching Frequency Selection Based on RON (R5)