Switch Mode PSU design

bertus

Joined Apr 5, 2008
22,266
Hello,

Only one of the outputs can be stabelized.
The second output is dependend on the stabelized one.

Greetings,
Bertus
 

Thread Starter

dhooker

Joined Jun 9, 2009
11
Mmmmh. Surely if I regulate the 24V to provide the 5V (@ 1A) I will be wasting about 20watts in dissipation across the regulator.
 

bertus

Joined Apr 5, 2008
22,266
Hello,

You can make a smps with two outputs by putting two windings on the transformer.
One for 24 Volts and one for 5 Volts.
You can only regulate one of the outputs.
The other will follow the changes in the regulated one.

Take a look at the attached PDF.

Greetings,
Bertus
 

Attachments

Last edited:

Tahmid

Joined Jul 2, 2008
343
Hi,
For such output, you can use flyback topology. You can take a look at Power Integrations' TOP series ICs, or UC384x series.
 

Tahmid

Joined Jul 2, 2008
343
Hi dhooker,
Here is a circuit for PSU for 24V @ 1.5A and 5V @ 1A. It is made using TOP246 from TOP-GX series of flyback converter ICs from Power Integrations Co. of USA. I personally made this circuit and still it is working fine. You can try this circuit.
I have attached it and also uploaded it to ifile.it. Here is the link:

http://ifile.it/rse43zu

Hope this helps.
Tahmid.
 

Attachments

Top