Separate outputs
We have designed dual output power supply with lnk623 and prototypes are running great.
Currently our transformer has shared output winding RTN pin as PI expert suggests.
Our design requirement has changed and we need two output windings to be separate.
How do we change our current transformer and feedback desing that the output voltages and total power remains the same?
PI expert doesn't seem to support design of this kind
-Jukka
Comments
Attached is PI Expert project, is that enough?
Right now your design is calling for 12T for the 5Vout, then adding 16 more turns for the 16 Vout. What you need to do is to have 12 turns for your 5 V output and another winding with 36 turns for the 16V. Try to wind the two windings as close as possible. You can start the two windings at the same time and in parallel wires. Finish and terminate the 5 V output winding and continue winding 24 more turns for the 16 V ouput.
Thank you for your reply.
I tried your advise by simply winding 16Vout on top of 5Vout and voltages were correct.
Is the point of parallel winding to get better regulation? I have to try that next.
If your power supply is working well the way you have your windings, then no need to try something else.
The idea for parrallel windigs is to try to have the best posible coupling from one winding to the other. In other words, try to have the same volts per turn on each winding.
Ok, thank you for your help
could you please post your schematic, power supply specifications and transfomer design? If I see the documentation I can give you better suggestions