ADVICE/SUGGESTIONS NEEDED >Purchased a 2 inch LED strip >Want

>>1149498
Connect a 12v battery to the + and -

>>1149580
I need it to be as small as possible. Is there any way a watch battery setup would work?

>>1149648
If it outputs 12v

The strip is 2" long?

>>1149658
Correct.

>>1149653
Again, I'm completely illiterate in EE.

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It will draw .175A* 2/12 = .029A = 29mA

To get 12V from regular batteries you'd need 12V/1.5V = 8 batteries in series. Not small.
(most batteres like watch, AAA, D are 1.5Volts)

An option would be to use a couple batteries and a boost converter.

Another is to try a 9V battery, they'll probably light up, but only ~2/3 brightness

The problem is that the strips come with built in resistors that were calculated for 12V.
For only 2" (how many led's is that?), and size being important, you might be better off just assembling LED's yourself so you could select the resistors to work with a lower voltage. You'd need a soldering iron or some ingenuity.

>>1149686
9v may be the way I go. I don't want it to run full strength.

>>1149686
>Another is to try a 9V battery, they'll probably light up, but only ~2/3 brightness
They won't light at all. They're not fucking resistors. They're diodes. They're not linear.

Get 12 volts from somewhere.

Ive never come across a coin cell that wasn't 3v. Put some in series

3(x)=12
Solve for x

>>1149750
12V diodes?
Several in series?
They're not single diodes with resistors?

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>>1149686
>Another is to try a 9V battery, they'll probably light up, but only ~2/3 brightness
nigga wut

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>>1149774
possible, but if they're in a strip they're not likely to be power LEDs. The 12V strips I've all seen are groups of three, and general purpose (cheapy) low and midpower LEDs have a Vf well above 3V.
A *good* white LED will have a lower Vf, but until you hit the minimal conduction voltage, you get no light at all. None. Emission is nearly a linear function of current, so look at the datasheet...

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OP here, way over my head with the charts and stuff. I am but a simple man. Pic related is what I bought.

>>1149789
Ooof, those are a pain in the ass.
Expect a few LEDs not to work out of the box. More will randomly fail over the next few years.
The 'waterproof' epoxy isn't. And it comes off and pulls LEDs with it. And gets hard and cracks.
Also, groups of 3 as expected, and they just use resistors to knock the 12V down. So, bloody inefficient on top of it; they're designed to run off a power supply on wall current.

In short, you got chinked. But hey, it was only $3!

>>1149802
but since 'half-ass' is the /diy/ motto, you can half ass it if you have no pride.

Four 3V coin cells in series. just hook 'em right up.
Won't power it for long but hey, we have no idea what you're using it for so good luck.

>>1149806
I have a gun sight with a fiber optic cable on top that illuminates the dot. I want to build an apparatus to illuminate it in low-light environments. It would be used very sparingly. Mostly for overcast conditions, and I don't actually want it to be full brightness.

>>1149859
....
And you bought.... 'something that lights up' to do that.
Why not buy a single low power LED, which you could run off a tiny hearing aid cell for years?

>>1149866
I said I was illiterate, a word which here means not very familiar with at all. I hate to beg any more but is there any possibility you could link me to the appropriate parts?

>>1149867
OK, fair enough.

Any 3mm high-brightness red led (it will have a forward voltage of about 2.2V), any lithium coin cell (forward voltage of about 3V), and about 1000 ohms for a resistor (get a miniature 1/10w). These parts will cost you less than a dollar. Maybe a switch--- add another fifteen cents.
The LED will be running at just under 1Ma (waaay under rated power). You could just pot it in some heatshrink and hot glue, or epoxy, or whatever.

Another possibility--- keychain flashlight. swap out the tact switch for a toggling pushbutton.

>>1149870
er, mA, milliamp, not Megamp :-)

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>Stacking aa batteries?
>using a 9v battery instead?

Has DIY gone retarded?

OP get a battery model 12V 23A
>or 12V 27A, but those are harder to find
>Walmart has the 23a's in stock at jewelry counter

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>>1149911
sup

>>1149870
One problem. Fiber optic is green. Red light makes it extremely unpleasant to look at. Lol would a green or white LED be much different?

>>1149937
yeah, they're usually right at or slightly over 3V.

>>1149943
So that being said what would my best bet be for a battery? 2032?

>>1149949
those'll be the biggest capacity common coin cells, yeah.

>>1149963
Wire 3mm green LED directly to power source (one I found has switch built in)?

>>1149985
No. That's the best way to burn an LED out. Remember the voltage/current curve is like a brick wall, and it changes as the thing heats up. The 'right' voltage when it first turns on will burn it out in a few minutes or seconds once it gets up to temp.
You absolutely have to have a limiting resistor.

>>1150016
Unless the power supply happens to be stable at or below the forward voltage of the LED. It happens with 3V coin cells.

>>1150016
Okay, I think I have it figured out.

I ordered the following:
http://www.ebay.com/itm/262690315146
http://www.ebay.com/itm/122101161110
http://www.ebay.com/itm/351189974674

If I'm not mistaken, the description of the LED component says there is a built in resistor.

If not I can get a 470 ohm 1/2 watt resistor and stick in there. Please tell me I did good.

>>1150049
should work, but battery + switch + resistors / leds is the simpliest at electronics and you already struggle with it. git gud

>>1150049
Led strip has resistors built in. I've attached a 12v car battery to a tiny strip and it worked no problem.

Why not try what anon suggested with the 23a12v batteries? They're small and will last much longer than button cells

>>1150065
I'm a blacksmith, not an electrician lol what can ya do

While I have the thread bumped, I'm thinking black instamorph for the housing.