Non-isolated configuration in Viper 25

[sam_niraj]

Posted on May 16, 2012 at 06:08

I have an application where i need to use Viper25H in non-isolated mode.

For reference generation I am using TL431. But the problem is that when TL431 is used for non-isolated configuration , power supply is getting into burst mode operation.

Can you please suggest  a reference circuit for using TL431 in non-isolated configuration specifically for Viper25H. The same configuration if used using Opto-coupler its working fine

As Viper25 does not have in it a error amplifier so i cannot used a simple resistor divider.

Using a zener based solution will have more impact on its temperature based tolerances.

So i have to use TL431 in feedback loop but using it for non isolated configuration is a bit of trick. Please suggest its urgent