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I'm designing a backlit custom picture frame, and I want to include the power supply (or the lack of one) inside the body of the frame.

The problem is, since the frame design is more or less thin, I don't have space to place a power supply, so I ran into this doubt, can I make a circuit to use a LED strip that connects directly to 220v without using a power supply?.

My knowledge of electronic is almost null, I ran into several links explaining how to power LEDs strips directly to 200v, but, I have honestly no idea what problems, advantages or disadvantages I could find, and the language used was kind of advanced for me.

Basically, I want to know if this is possible, and what is required to do so.

Please explain to me like If I'm 6 years old, thanks!.

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    \$\begingroup\$ Let me just restate Kamil's nice answer (+1). Buy a wall wart that puts out a nice safe DC voltage to power your LED's. (Come back and ask how to hook it up.) \$\endgroup\$ – George Herold Nov 25 '14 at 0:11
  • \$\begingroup\$ I would, but I need one that is thin enough to fit in there. \$\endgroup\$ – Artemix Nov 25 '14 at 0:24
  • \$\begingroup\$ Can't you hide the wart somewhere, and just have wires going to the led's? \$\endgroup\$ – George Herold Nov 25 '14 at 0:34
  • \$\begingroup\$ If it goes into the wall... no. \$\endgroup\$ – Artemix Nov 25 '14 at 1:15
  • \$\begingroup\$ At least the pictures will be interactive. \$\endgroup\$ – geometrikal Nov 25 '14 at 1:17
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Explanation for someone who needs answer "like for 6 years old":

It is possible, you can build simple circuit for LED, but don't do this. Just use old phone battery charger or some external power supply because if you wont - you need serious and robust insulation there. This is more problematic than just using power supply and some resistor.

AC mains is not only dangerous voltage. It is also high energy source. If your frame falls, casing may break and wires connect to each other - it may cause short circuit and fire.


However - you can build very sturdy/robust casing and make sure that wires will not connect each other no matter what (hitting ground, pulling cord) - you can use diode + 1W resistor or diode + capacitor + resistor circuit as current limiter for LED (small LED, not power-LED).

Just search web for "led powered from mains" and stay away from Instructables. I saw many irresponsible and dangerous tutorials there. Here is one example:

enter image description here

Be careful with LED if it explodes. LED diodes contain arsenic which is notoriously poisonous to multicellular life.

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    \$\begingroup\$ +1 for the instructables comment. Full of rather dodgy things written by people that really don't have the slightest clue what they're doing. \$\endgroup\$ – Majenko Nov 24 '14 at 22:49
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    \$\begingroup\$ @Majenko-notGoogle I'm wondering why there is no "report dangerous idiot" button on Instructables. Or maybe it is visible after login. \$\endgroup\$ – Kamil Nov 24 '14 at 23:03
  • \$\begingroup\$ Thank you for your advice, but I would honestly need some sort of step-by-step guide or tutorial to make it work :p. And, yes, I plan to insulate the strips completely. \$\endgroup\$ – Artemix Nov 24 '14 at 23:10
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    \$\begingroup\$ @Artemix I have added very important information. Simple current limiters mentioned in my answer are for low current (10-20mA) LEDs, not power LEDs. For power leds you have to use dedicated LED power supply. \$\endgroup\$ – Kamil Nov 24 '14 at 23:24
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    \$\begingroup\$ @Artemix 5050 is just size :) Oh dear, you should avoid mains. Seriously. \$\endgroup\$ – Kamil Nov 24 '14 at 23:35
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Design your frame around a 5v supply. This basically means an LED and a resistor in series. Connect this to a USB cable, the flat end, pins 1(power) and 4(ground). You can get the cables very cheap at any electronic gadget supplier.

While you are there getting the cable, also get a USB charger. Small, and readily available for under €10.

Building a 220v -> LED power supply that fits in a picture frame is not impossible. But it is not easy, and the development and testing of such a supply exposes lethal voltages. If you need instructions, you shouldn't be doing it. Since commercial power supplies are readily available lets just use one of them instead.

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  • \$\begingroup\$ I'm interested about the USB charger idea, I will dig into it. About the power supply, I need it to be something like 1"x3-5". \$\endgroup\$ – Artemix Nov 24 '14 at 23:32
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    \$\begingroup\$ USB chargers are readily available in sizes you can close your hand around. To clarify - the charger still plugs into the wall. Your cable from the frame ends in a USB plug that goes into the charger. \$\endgroup\$ – paul Nov 25 '14 at 4:52
  • \$\begingroup\$ Oh I see, then it wont do unfortunately, since I need it to be power-supply-less. \$\endgroup\$ – Artemix Nov 25 '14 at 14:18
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    \$\begingroup\$ @Artemix you asked "how do I do this" and everyone has said "don't do that". This should be a strong sign that what you want to do has serious (and dangerous) issues. \$\endgroup\$ – paul Nov 25 '14 at 21:00
  • \$\begingroup\$ Paul, yes, I desisted of the idea of doing it. I just wanted to give it a try. \$\endgroup\$ – Artemix Nov 25 '14 at 21:07

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