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I have an RGB Led strip that I want to use for just white light. I currently use an arduino with some transistors to control each colour. I have now no need to have different colours and I think my LED strip is not as bright as it could be due to the transistors I am using.

If I want to just use it as a white LED strip, can I just connect the +12 volt to +12v on the strip and the RGB pins to ground without the transistors or the arduino?

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    \$\begingroup\$ Yes, probably. - \$\endgroup\$ – Olin Lathrop Sep 6 '17 at 17:02
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    \$\begingroup\$ So you want to display the color "white" on a RGB LED strip? Why not just get a white LED strip instead? It's probably cheaper and would consume less power. \$\endgroup\$ – KingDuken Sep 6 '17 at 17:16
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    \$\begingroup\$ Its a case of doing it with what I already have unfortunately. \$\endgroup\$ – Bruno Sep 6 '17 at 17:18
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    \$\begingroup\$ no link to LEDstrip specs? No DMM readings? no crystal ball. There are many versions. \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Sep 6 '17 at 17:44
  • \$\begingroup\$ You can do it. The arduino helps you control the intensity of each colour, if you want Maximum intensity on each colour, you will most likely get a whitish colour as a result. It's just more fun to have varying colours sometimes! \$\endgroup\$ – Sebastian Scholle Sep 6 '17 at 19:29
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I have successfully done that very thing in the past to replace a broken light bulb in my car for a fraction of the price.

It probably depends on the specific strip and LEDs, for me the color was not a "perfect" white, as expected, but close enough.

If you are worried about it working or not, and have some LED to spare, just cut one LED off the strip and run a test on it. Then you can proceed with some peace of mind to the whole strip.

I hope this helps.

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Typical dumb RGB led strips are nothing more than the leds and a resistor on flexible printed copper tape. You can directly connect them to the V+ and ground for a fixed color.

As a fyi, as long as you properly size the transistor and it's base resistor to saturate at the load you are carrying, the voltage drop of the transistor will be minimal and you would not really see any difference in the led strip brightness.

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Typical 3S or series RGB Ledstrips use ~12V+/- 10% and about 0.5A per channel per 5 reel. The switch needs to be FET type for low RdsOn=<100 mOhm . Current limit is set by design by series R's in each section.

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  • \$\begingroup\$ Sure, but it's not clear whether the OP even needs switching at all. \$\endgroup\$ – Reinderien Sep 7 '17 at 13:10
  • \$\begingroup\$ This explains why it possibly did not work with a single BJT ( low current gain when saturated) and what will work with a FET or a switch. \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Sep 7 '17 at 14:44

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