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I would like to run 16.4' of 12V LED strip lighting with a 12v deep cycle battery. The strip lighting says it uses 1.5W per foot so I'm expecting that I'll need to provide about 2A. I was really hoping that there would be a ready made product to regulate the current efficiently, but so far no luck (if you happen to know of a product available to do this I would really appreciate a link). What would be a common way to accomplish this task?

Thank you, Trevor

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    \$\begingroup\$ You can power it directly. The LED strip has built in resisters and is typically not regulated further. It is intended for a car 12V connection. There will be some slight brightness fade as the battery power gets used up but not too noticeable. \$\endgroup\$ – Passerby Aug 21 '15 at 1:26
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Can you reconnect strips in series 12+12=24V, then you can use boost dc-dc converter from your battery around 12V to stable 24V?
This arrangement will give you stable light that is not dimming during battery discharge. That's what I did with my emergency light - there is 6 strips with 3 LED each. I connected three of them in parallel (12V), connected other three in parallel(12V), and connected those 2 pairs in series which gives 24V. Then I bought this boost converter (about 3 USD) and it still works perfectly.

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Answering your question: you can't use a 12v battery to power a 12v led strip directly. a fully charged lead acid will have 13.8v which will burn out your led strip if you are doing so. You don't need a current limited device. What you need is a voltage regulator. You need exactly 12v to run your led strip. I will suggest a buck dc-dc converter. you can buy one in ebay for $3; cheapest way to go is to use 3 diodes. 0.6x0.6x0.6=1.8. it will drop your 13.8v battery to 12. making it more safe to run your led strip, but the problem is when the battery voltage drops, so as your led brightness, and another problem for simple diodes is energy efficiency; 3 diodes will produce many heat and waste your battery life.

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  • \$\begingroup\$ These strips will work without issue up to 14V... And at their nominal 12V, a 1.8 ~ 2.1V will bring it down to 10V, near the low end of the led strip range. \$\endgroup\$ – Passerby Aug 21 '15 at 4:29
  • \$\begingroup\$ It surely will, and it also will limited the life spans of led strip because of over-heating overtime. \$\endgroup\$ – Atmega 328 Aug 21 '15 at 4:32
  • \$\begingroup\$ Not significantly. At 12V the Red and Blue of a led strip run at 17mA, not 20mA. And the battery will go from 13.8V to 12.5V relatively quick. Even under charge like in an active car system, these led strips have years of life. \$\endgroup\$ – Passerby Aug 21 '15 at 4:34
  • \$\begingroup\$ significantly, if the led strip is designed to run at 12v at 100% brightness which is reasonable given the fact that brightness controller is very cheap these day. please notice that not all led strips are the same, thus it's only smart to run 12v led strip with regulated 12v power supply, both for safety and lifespan. Even so, a good life span led strip shouldn't run at 100%. We installed LED strips that run at 70%. When it's not warm to touch, it will have a longer life. \$\endgroup\$ – Atmega 328 Aug 21 '15 at 4:43
  • \$\begingroup\$ But that's the thing. Given typical resistor values and led forward voltages, they are not at 100% at 12V. These things were produced for automotive usage in an unregulated environment. \$\endgroup\$ – Passerby Aug 21 '15 at 4:47

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