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TNY289 , 3 output SMPS

Posted by: atulbhakay on Mon, 08/02/2021


I have designed a power supply with the following specs

Input = 85V to 265VAC

Output 1 = 5V / 2A

Output 2 = +15V / 0.2A

Output 3 = -15V / 0.2A

The design details are attached herewith.

The power supply works well when the main 5V output is loaded to 0.5A. However, on increasing the load on this main output to 0.6A and loading the +/-15V to 0.15A, and on directly switching ON the power supply at 230VAC, the SMPS was NOT turning ON i.e not giving any output

Kindly verify the PI expert file that I have attached and the transformer details and schematic and advise


Atul Bhakay


Submitted by PI-Lupin the Third on Mon, 08/02/2021



Thank you for using our product. 


I think you forgot to attach the PI Expert file. Please kindly upload.


Thanks and regards,


PI-Lupin the Third

Submitted by atulbhakay on Tue, 08/03/2021

Hi Lupin,

I have attached the PI expert file after "export all to pdf"

Is this what you wanted ?

Else advise as to how to attach the .uds file


Atul Bhakay

Submitted by PI-Lupin the Third on Tue, 08/03/2021

Hi Atul,

Thank you for sending the attachment. One of our representatives will reach out to you and attend your inquiry in a while.



Submitted by PI-Kryten on Sat, 08/07/2021


Thank you for considering Power Integrations for your solution.

Kindly attach PI Expert file as excel. Please also include a .pdf version of your schematic.


Best Regards,