Simple dual output supply using tny267

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I have to supply my power analyser design. I need one output for main parts (analog, logic, LCD, etc.) and one for isolated RS485 interface.
I was looking at some similar reference designs and i create simple solution using TNY267 and HAHN V50116 transformer.

Can someone with more experience (this is my first SMPS design) just take a look at my design and comment it?
My idea is to use 12V output with some LDO's to provide 5V and 3V3 to main parts and second 5V output just as it is to supply isolated side of RS485 transceiver.

Bill of materials402.92 KB
SCH.pdf43.51 KB

Hi mkowalski94

Good Day!
Thanks for taking time to consider to use Power Integration products.

We need to establish the complete specification in order to review properly the design.
What is the AC input voltage range?
What is the output current for the 5V output?
What is the output current for the 12V output?





AC input will be in range of 220 - 240 V ac

12V output current 300mA max
5V output current 50mA max

Thanks fo answer!

Hi mkowalski94

Good Day!
Is there any reason of choosing TNY267GN TinySwitch II.

We would like to recommend to use TinySwitch LT or TinySwitch III

Application notes for TinySwitch LT can be found on below website

The application notes shows step by step process on the design of the Flyback Converter using TNY LT or TNY III

We have a online tool on how to calculate critical parameters of a flyback desing using
TinySwitch LT or TinySwitch III

Online tool can be found on below website

This online tool is free. You will just need to register.

I can help you if you have technical concerns or question on how to use the online tool..