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Can I use a 4.5VDC power supply with 1A with a device that should have a power supply with 5VDC and 1A?

I have a hdmi splitter that needs 5VDC and 1A max but I can't find those ratings of voltage, only 4.5V, will it be enough? I measured the voltage and it's 4.57V. From what I know I don't think this will be a problem.

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The odds are against this working. +5VDC specs are commonly a +/- tolerance of 5%, or +4.75V on the low side. With no load the supply you have cannot meet that requirement; with a load that voltage will be even lower. – sawdust Nov 21 '12 at 20:29

It may work, it may not work.

Basically, for things to work you would need to:

  1. Have the same voltage.
  2. Be able to supply at least the same amperage.
  3. Have a correct connector (center pin negative vs center pin positive is not always obvious, but is a good way to release that magic smoke. So make sure polarity matches).
  4. Same kind of power (AC vs DC).

Your voltage is close but 4½ volts is still a full fifth less then 5 volts. That may be to much of a difference. Noone is going to guarantee that that will work without knowing much more about whatever it is you are trying to power.

Bottom line: Unless you do not care about replacing your HDMI splitter or the devices connected to it I would not try it.

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I like how you framed your closing sentence – Akash Nov 21 '12 at 20:29
I was going to mention possible overheating do to 20% voltage difference, fire danger and leaving the power on when people are away. But while try that might have been over the top. (Still, it is a reason I would not try it). – Hennes Nov 21 '12 at 20:31
Thanks! Sounds good all the info provided. I tried it for some short period of times and it works, the splitter doesn't have until now overheating problems but anyway I only tried it for an hour. – user175061 Nov 21 '12 at 21:01

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