Hallo all,

Is there anyone who did a project with LT3748 Flyback converter?

I am designing a circuit with LT3748 such that the input voltage is standard 24V and the output voltage is 12V@2.5A. I designed my own planar transformer that had Nps 3:2. The problem, I am facing is that there is lots of power wasted in the mosfet. Is there a way to reduce the losses in the mosfet without adding a snubber circuit to the design?

and also the output is not exactly 12V insted 11.5V at light load conditions(R=5Ohm).

I am simulating for the worst case senario that the coupling factor is 0.98 instead of 1, since I dono wat is the exact Coupling factor of the transformer yet!!

Thank you.

 

https://www.we-online.com/web/en/in...s/versteckte_seiten/lt_kits/LT3748_750108.pdf

Demo boards, their schmatics/manuals might be of use -

https://www.digikey.com/catalog/en/partgroup/lt3748-demonstration-boards/59219


Regards, Dana.

 

Thank you for the reply. I already have this

The problem is that if I set the voltage exactly 24V, the compensation network should be changed and how to change the compensation network so that the output is 12v for small loads(10 ohms) and big load (100 ohms) ?

As I said in my previous post, how to compensate for a 0.98 coupling factor instead of 1 ?
The demo circuit has würth transformer and i dono the coupling factor of it!!! In reality the coupling factor can’t be exactly 1.

And during the initial starting phase of the circuit the power across the FET is around 300W, can anyone tell me why is that?