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anyone knows if it's possible to use a led strip with 3 pins without a controller? I got this 1,5 meter strip without controller, I don't know if I should've bought it or not...

please see attached images, there's a (+), (-) and (+3.6v) pin how can I use it without a controller, just a battery?

LED element and resistor (?) 3 pins connector specifications

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Your strip only needs a 3.6V DC power supply.
It appears you have one 20Ω resistor for each LED.
This would power each LED with 30 mA or 90 mW per LED (3Vf x 0.03 A).
If this is true there would be about 25 LEDs on the strip (2.3W / 90 mW = 25.5).


A strip that requires a controller will have IC(s) on the strip.

enter image description here
source: witop-tech.com


Or have RGB LEDs that look something like this.

enter image description here
source: Adafruit


how can I use it without a controller, just a battery?

You can likely use just the + (red circle) and - (green circle) pins to power. I'm not sure about the 3rd pin. Not likely an earth ground as there are no lethal voltages. It may be unused. Most likely it is an additional pin for the 3.6V.

enter image description here



3.6V Batteries do exist. The most common being an 18650 Li-ion cell.
These batteries start at about 4.2V and discharge to 3.0V.
More likely it is meant to be powered with a 3.6V AC-DC adapter.
Battery powered LEDs dim as the battery voltage drops as it discharges.

enter image description here
source eemb.com LIR18650 datasheet



I did find someone (in France) selling these but they appear to be 12V.
Leroy Merlin

enter image description here


NiMH will much better than alkaline.
Notice at the end of charge the voltage is still 1.1V.
It is best not to allow to discharge to zero volts but is much more forgiving than LI-ion.

enter image description here
source: Panasonic HHR120AA NiMH datasheet

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  • \$\begingroup\$ Could you please provide links to the sources of your graphics or some other form of attribution? \$\endgroup\$ – Elliot Alderson Oct 27 '18 at 15:36
  • \$\begingroup\$ Thank you! working great from 3 AA batteries \$\endgroup\$ – cmpscabral Oct 27 '18 at 15:45
  • \$\begingroup\$ Make sure they do not get too hot. At 4.5V you are driving them at 75 mA. That's 2.5x when driven with 3.6V. You should be able to continuously hold your finger on/near the side of the LED without discomfort. \$\endgroup\$ – Misunderstood Oct 27 '18 at 15:53
  • \$\begingroup\$ Would help to use NiCd or NiMH, those are 1.2v per cell. \$\endgroup\$ – Harper - Reinstate Monica Oct 27 '18 at 21:14
  • \$\begingroup\$ 3 NiMH would work very well, appended more info to my answer. \$\endgroup\$ – Misunderstood Oct 27 '18 at 21:29

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