#Electronics nerds of the fediverse, what's the most efficient way of powering really low power devices from the mains?
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#Electronics nerds of the fediverse, what's the most efficient way of powering really low power devices from the mains? I have a board that consumes a peak of about 2.4w, but most of the time only consumes 0.35w. Having a mains to 3.3v or mains to 5v adaptor that is drawing more than the device most of the time seems a poor choice.
Any recommendations?
@quixoticgeek What kind of project is this? Are you comfortable designing PCBs with mains voltages? If so, there are PCB mount AC/DC modules (E.g. Meanwell and Myrra) which only consume 75mW at no load. You may be able to do better still with a bit of searching.
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#Electronics nerds of the fediverse, what's the most efficient way of powering really low power devices from the mains? I have a board that consumes a peak of about 2.4w, but most of the time only consumes 0.35w. Having a mains to 3.3v or mains to 5v adaptor that is drawing more than the device most of the time seems a poor choice.
Any recommendations?
@quixoticgeek IKEA's SMÅHAGEL supposedly only draws 30mW when unloaded and provides up to 1A/5W.
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@moof @quixoticgeek this was my thoughts. Have a buffer like battery or elco, and only switch on supply when low.
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@quixoticgeek IKEA's SMÅHAGEL supposedly only draws 30mW when unloaded and provides up to 1A/5W.
@pndc ooh, where do you see the 30mW number I'm not spotting it on the ikea website anywhere obvious. But that would be ideal.
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@moof @quixoticgeek this was my thoughts. Have a buffer like battery or elco, and only switch on supply when low.
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#Electronics nerds of the fediverse, what's the most efficient way of powering really low power devices from the mains? I have a board that consumes a peak of about 2.4w, but most of the time only consumes 0.35w. Having a mains to 3.3v or mains to 5v adaptor that is drawing more than the device most of the time seems a poor choice.
Any recommendations?
@quixoticgeek At a guess, a solid state transformer (basically most modern phone chargers) is going to be the best bet, >90% efficiency. But thermodynamically you *have* to have losses, and anything converting mains (capable of kWs) down to single Watt range is going to seem very inefficient, the actual usage is comparable to the very minor loss in the transformer.
Rechargeable batteries, perhaps? With a controller you could have short bursts of charging for hours/days of usage? -
@kim @quixoticgeek POE is a nice idea.
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@quixoticgeek IKEA's SMÅHAGEL supposedly only draws 30mW when unloaded and provides up to 1A/5W.
@quixoticgeek I made a slight error, but not in a bad way. The datasheet is in the product bumph PDF. The one I linked to is actually 70mW at idle and provides up to 17W across 3 USB-A outputs. There is also a model which is 30mW at idle with 5W on its single USB output which is the PDF I was looking at: https://www.ikea.com/nl/en/p/smahagel-power-supply-kit-80604096/. There are a few other charger options with different idle draws and maximum power outputs in the general category: https://www.ikea.com/nl/en/cat/usb-chargers-40844/.
The product bumph PDFs are buried behind a load of clicks; thanks JavaScript. I clicked on "Product Details" then "Assembly and documents" and from there there's a PDF download link.
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@quixoticgeek I made a slight error, but not in a bad way. The datasheet is in the product bumph PDF. The one I linked to is actually 70mW at idle and provides up to 17W across 3 USB-A outputs. There is also a model which is 30mW at idle with 5W on its single USB output which is the PDF I was looking at: https://www.ikea.com/nl/en/p/smahagel-power-supply-kit-80604096/. There are a few other charger options with different idle draws and maximum power outputs in the general category: https://www.ikea.com/nl/en/cat/usb-chargers-40844/.
The product bumph PDFs are buried behind a load of clicks; thanks JavaScript. I clicked on "Product Details" then "Assembly and documents" and from there there's a PDF download link.
@pndc Brilliant, thank you!
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@quixoticgeek @moof how long does it need to run?
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@quixoticgeek @moof how long does it need to run?
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