DC/DC Converter Help

Discussion in 'Power Electronics' started by darksavior, Aug 14, 2016.

  1. darksavior

    Thread Starter New Member

    Aug 14, 2016
  2. CEJones

    New Member

    Feb 12, 2016
    The output voltage is set using the voltage divider resistor network from Vout to Vfb to ground. The internal voltage reference is 0.8V. To calculate this you can set up a proportion Vfb/Vout=R2/(R1+R2).
    One note on this, the sum of the two resistors must be less that 50kohm due to reference bias currents. This reference feeds the internal error amplifier, saying when the output exceeds its nominal voltage, the feedback node exceeds the 0.8V and the switcher will convert the duty cycle as needed to compensate.
    Hope this helps.
  3. Bernard

    AAC Fanatic!

    Aug 7, 2008
    I would connect a pot from output. 19, & ground, 21,wiper to pin 20. Adjust to 2.7V. Replace with fixed values
    if desired.