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How can I power a 12v LED strip with a 3v coin battery? Answered

I am working on project with a flashing led strip, 6 bulbs in total. The circuit includes a 555 timer.  At first I was using a 9v battery but then realised that battery is way to big. A coin battery (CR2032) would be perfect. How can I power the LED strip using the 3v coin better? I am pretty new to circuitry so any help would be greatly appreciated. Thanks in advance. 


Not easily on a single 3 v cell - 4 x 3 in series volts is 12 volts BUT they won't last long because of the current they will draw from the battery.

A joule thief (perhaps what your thinking of will also not work because of the relatively high current need. Perhaps if you tell us why we can suggest some way round it.

Still getting used to the forum. I replied above.

I’m having a similar issue ,
I need to power a 24v UV led strip
But I need the battery to be small
I’ve tried 8 3v coin batteries in series but nothing is working
Is there anyway I can make it work

Thanks for all the suggestions. I really appreciate it. I'm basically making a dog collar with a flashing LED strip. My dog is quite small so I don't think it's a good idea to have him running around with a 9v battery attached to his neck. The strip I'm using is a basic 12v strip with three bulbs in between each area where you are able to cut. That's one reason why I don't think two coin cells would work.

A 3v batt on its own isnt going to do anything on a 12v led strip, you'd need a 12v battery, ie 4 of those 3v's stacked on top of each other.

I read something about transistors. Would that help with amplifying the voltage? I understand that a 3v battery isn't going to work but I've seen them work in other projects using the same LED strips. There must be something I'm missing in the circuit.

No, you cannot amplify the voltage that way. The problem is a coin cell contains a certain amount of energy, which you can either use quickly, delivering a lot of power, or slowly, delivering less power.

No, unfortunately there is no free lunch. :( Amplifiers can only output voltages "in between" the supply. (a 5V amp can only output 0-5V.*)

However, there is such a miracle device called a DC to DC converter, which can convert lower voltages to higher ones and vice versa, however, at the cost of current. If you want to learn some fundamentals on electronics, check out my playlist here:



3 years ago

A tiny 3V battery has to high internal resistance, so it cannot deliver a whole lot of power, and it will probably not last long at all, since likewise it does not store much energy.

You can probably get away with using 4 of them stacked, so they are in series and the voltage adds up. (3v + 3v + 3v + 3v = 12v) Can we see some links or pictures of the LEDs you want to power? If they are the standard 5mm LEDs, then I think it will be fine.

Change your circuit to run 6V.
This way you can use 2 coin cells, all you need is to change the values for the LED resistors as long as the rest of the ciruit is not voltage dependent.