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Power Supply Not complying with the new DOE Level VI Performance Requirements

Power Supply Not complying with the new DOE Level VI Performance Requirements

I'm working on a VERY custom 120VAC to 5VDC power supply and I've looked over the new DOE efficiency standards and I've noticed that they have changed the Max power in the No Load mode to 100mW for my power output. Given the complex design of the power supply I do not think that I can meet this condition at this time. What are the repercussions of not meeting the DOE efficiency standards? I would still like to get this power adapter UL certified so I'm hoping this won't be a problem there either. Any insight would be helpful!

RE: Power Supply Not complying with the new DOE Level VI Performance Requirements

If there is a big difference between the running power demand and the 'powered-down' demand then the typical solution is a second power supply. One that supplies just enough power to detect a "power up" signal from the large supply's consumer. Or possibly you can use the second one to 'blindly' keep the output stage fully charged providing the main supply some time to come on-line.

You realize there are 1 and 1/2W isolated supplies that have 5kV isolation and come in SMD footprints?

Keith Cress
kcress -

RE: Power Supply Not complying with the new DOE Level VI Performance Requirements

EEMan, Interesting post. Thanks for the heads up. I just looked up the new 2016 DOE requirements. Yikes. The 100mW which you mentioned is 200mW less than the old 300mW standard. That in itself required everyone to redesign input stage filters. Let's see: 0.2 W savings x 24 hrs x 365 days = 1.73kWh saved per year. Multiply that by an average of 15 cents/kWh and we get 26 cents savings per year. This seems totally negligible to me.
Will the cost of each wall-wart go up by more than 26 cents to get the extra circuitry in there?
Did the government get input from major suppliers of such devices for their opinion as to what this extra cost will be?

Darrell Hambley P.E.
SENTEK Engineering, LLC

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