120 - 277 VAC 1.5 W Design

Posted by: Bouwser on 05/28/2015

Hello,

We are looking for a low cost power supply. Input voltage 120 - 277 VAC (nominal), 1.5 W. I have found a reference design on your website for a 120 - 277 VAC supply, but it is supplying 20 W. This is much more than we need.

The application is a wireless controller for an LED Luminaire.

-It does not need to be Class 2.

-Can we avoid using a transformer or use one that is already readily available? (Our current design uses a custom transformer and we are unhappy with the quality and are having difficulty with the manufacturer addressing the quality issue.)

Any help is greatly appreciated,

Brent

Comments

Hi Brent,

Thanks for Posting your question. Yes you can design 1.5 W Output power supply based on our Products. 20 W reference design is overkilled.

Please see below one of our 1.2 W reference design:

http://ac-dc.power.com/sites/default/files/PDFFiles/epr8.pdf

http://ac-dc.power.com/design-support/reference-designs/design-examples/di-153-125-w-low-input-voltage-range-power/

Also Please download our PI Expert, enter your spec's it will provide you optimised design solution and Magnetics design. Please let us know, if this helps. Any questions, feel free to write back.

Regards,

PI-KSAN

Hi PI-KSAN,

Thank your for your response. I really like the epr8 design. I was also looking at di-139. I need a supply at 12 V and 3.3 V, but was planning to buy an additional switcher to go down to 3.3 V from 12 V, but if I can do it all in one that is even better.

However, I need ~40 mA at 12 V and ~200 mA at 3.3V. Is it possible to change the resistor values and get more power for the 3.3 V rail?

thanks,

Brent

Hi Brent,

Yes you can get more power by changing the transformer design. use EPR8 as a reference design and download our PI Xl's Transformer design Spreadsheet. Enter the the Transformer spec's as per the EPR report and modify it as per your power specifications. Please let us know if this helps

Regards,

PI-KSAN