Product: Power Source: AC DC Conversion
DC low-power output from high-power devices   (+13)  [vote for, against]

Devices which use a reasonable amount of power like amplifiers, computers, etc. contain big, chunky transformers which could easily cope with the demands of two or three low-power (say 4, 6 or 9 V DC, at max 2A) devices which currently use their own "wall-wart" transformer. All that would be needed would be a few extra taps on the transformer and some sockets on the back panel. You'd then avoid the inefficiency and cost of having separate transformers for every device.
-- hippo, Jul 31 2008

12 volt house 12_20volt_20house
I know this idea is not dissimilar to "12 volt house" but I think starting to sell devices with standard DC power outputs is easier that retrofitting 12V cabling to everyone's house. [hippo, Jul 31 2008]

Your computer power supply already produces the requisite voltages in a fan cooled power supply. If only it had a power output setup. You could use jumpers to power the 15 peripherals that need individual warts. I think it's a good idea.
-- WcW, Jul 31 2008

... turns ratio... rectification... current limiting... switch mode... proprietary connectors...

I'll let the electronics types fill in the gaps, lest I appear foolish. I do have my doubts about how easy this proposal would be though.
-- Texticle, Jul 31 2008

USB? IIRC, it's good for 100mA (or 0.5A with high power mode) at 5Vdc, +/- 5%.

This may be suitable for many lower-power devices. Also, connectors are low-cost, and pinout is standard (which is more than can be said of the huge variety of wallwart connectors!) Presumably adaptors can be made if required.
-- csea, Jul 31 2008

the issue here is that everyone wants to ensure the performance and durability of their product. from a warranty and service perspective it's a nightmare.
-- WcW, Jul 31 2008

I actually tried powering some of my home appliances using a computer power supply recently, and found my TV, wifi router and mini-itx system used a lot more power when running from a single computer PSU than using individual power bricks. I think the PSUs I tried (three of them) are inefficent at low loads, and since you wouldn't want your computer on all the time to power your other equipment this might be a problem. A generic 12 volt transformed designed for this job might do better.
-- Srimech, Aug 01 2008

used to be a common item in equipment racks was a wall-wart eliminator: a 1/2U 9V power-supply with many outlets.
-- FlyingToaster, Mar 29 2009

The only other thing in order is to select/agree upon a universal connector.
-- Jscotty, Mar 29 2009

The concept of additional transformer taps doesn't really apply directly to a regulated switching power supply—not much uses a plain old transformer anymore. But computer power supplies already produce multiple voltages—the ATX standard currently specifies 3.3 V, 5 V, and 12 V, and used to specify -12 V as well. And the idea of ports on a computer to provide power to small devices is well baked by USB.
-- notexactly, Apr 11 2019

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