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

4.2 Analog Duty Cycle Control Using APWM

The TPS92643EVM-204 is by default setup without APM. Testing the analog duty cycle control is performed by applying a power supply to APWM test pin (TP9). The duty cycle is at the minimum at 1 V (0% duty cycle) and linearly increased until 2.5 V (100% duty cycle). For example, if APWM is set to 1.75 V, then the duty cycle is set to 50%. The PWM frequency is 1.6 kHz.

Figure 4-3 Test Setup for APWM