Power Supply Question - Electronic Circuits Projects Diagrams Free

brittam · 12th July 2007, 05:13 AM

Hi!

My question is one about a power supply.

First, I just want to give you a quick background about my project.

I have assembled 4 separate electronic LED light boxes, each of which in their original state were powered by an Input 120 VAC 60 hz 12w with an output of 8v AC 1 amp power adapter into one unit by joining the internal power cords of each unit together.

My question is~~~

What power adapter would I need to power the now 1 unit safely? (in terms of electrical requirements)

Thank You,
Graham

Hero999 · 12th July 2007, 09:54 PM

LEDs ideally require a constant current supply rather than a constant voltage supply.

Using a resistor in series with the LEDs is alright for low power levels if you're not bothered about efficiency.

More information is required here, at the very least you need to give:
Forward current?
Forwars voltage?

The above can be found from the datasheet; if you don't have access to this then you can normally estimate it from the colour of the LEDs. This can be found from Wikipedia:
http://en.wikipedia.org/wiki/LED_circuit

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12th July 2007, 05:13 AM	(permalink)
brittam	Power Supply Question Hi! My question is one about a power supply. First, I just want to give you a quick background about my project. I have assembled 4 separate electronic LED light boxes, each of which in their original state were powered by an Input 120 VAC 60 hz 12w with an output of 8v AC 1 amp power adapter into one unit by joining the internal power cords of each unit together. My question is~~~ What power adapter would I need to power the now 1 unit safely? (in terms of electrical requirements) Thank You, Graham

12th July 2007, 09:54 PM	(permalink)
Hero999	LEDs ideally require a constant current supply rather than a constant voltage supply. Using a resistor in series with the LEDs is alright for low power levels if you're not bothered about efficiency. More information is required here, at the very least you need to give: Forward current? Forwars voltage? The above can be found from the datasheet; if you don't have access to this then you can normally estimate it from the colour of the LEDs. This can be found from Wikipedia: http://en.wikipedia.org/wiki/LED_circuit __________________ I also post at the following sites: http://www.stop-microsoft.org http://www.heated-debates.com Screen name: Aloone_Jonez