I'm trying to build a 48V-400V full bridge dc-dc converter. I'm using sg3525 as pwm IC and trying to get isolated feedback from output and planing to do it with TL431.

When I study on it people are suggesting to apply a type 3 compensation on it for several reasons about stability, I'm not good at control systems and trying to find some sources or examples about calculations but I can't find a suitable source to learn how to do it so I need some help about it.

Can any one please share some sources about calculations and design with me please, I've found many circuit examples but I can't find exact formulas and calculations to calculate compensating components or error amp in IC.

I'm also open to your precious advices about whole process.

Thank you.

  • 1
    \$\begingroup\$ The full-bridge dc-dc converter is a buck-derived topology and requires a type 3 compensator when operated in voltage-mode control. The TL431 is not best choice for loop compensation especially for a type 3 configuration unless you disconnect the fast lane. Have a look at this PPT (cbasso.pagesperso-orange.fr/Downloads/PPTs/…) but also this one in which all compensators are detailed (cbasso.pagesperso-orange.fr/Downloads/PPTs/…). \$\endgroup\$ Nov 27, 2019 at 12:31
  • \$\begingroup\$ Thank you @VerbalKint, I'll work on them. \$\endgroup\$
    – Das D.
    Nov 27, 2019 at 19:20


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.