need to design smps with i/p (20-265)vac

Posted by: uday mistry on 10/20/2014

Dear sir,

I need to design the SMPS using TINY III.

I/p: (20-265)VAC

o/p: 12vdc@ 100mA

5vdc @ 250mA

i am using the PI expert software for the same but unable to find any design.

kindly provide me any suggestion or test circuit of examples.

Thanks & Regards,

Uday Mistry

Comments

Do you need isolation from line

If you need it then you need to implement the circuit listed in the below link

http://www.powerint.com/node/234

If you do not need then you can desig witha buck converter

let me know if you need isolation

Hello,

I have littelbit confusion about the link which you have send it to me.

just let me know the how to calculate the value of R1,R2 & R3?

can we use that floating constant current supply to TOP 244 series or its for the TNY III only?

please suggest me the alternate solution for the same.

That buck converter idea also please suggest to me.

- Uday Mistry

The Idea of the buck does not work. I am sorry is my mistake. It does not work becasue at low line (20 VAC, 28 V, ) the voltage at the controller is only 16 V, So it is not work

You use the CC source in the link I indicated to you. Use the formula indictaed in the link. Use I = 600 uA. The you play with the values of zener and other compnents to obtain 600 uA