Looking for some guidance here. I have 600 5V ws2811 LEDs and I want to run them from a vehicle so about 15v. Can anyone help me figure out the easiest way to reduce the voltage for the max current draw (I figure the current to be at most 18 amps)? Is anyone aware of a low cost vehicle voltage regulator that will do what I am asking or is a DIY project to build a DC - DC Switching power supply?
For a similar project I ended up cheating and getting a 800w 120v inverter from Amazon, then bought a 40A 5v power supply off of ebay. It is definitely inefficient and takes up more space, but it gets the job done.
A regulator from http://www.vicorpower.com/ is also another option, and are designed for more commercial applications. You can find a lot of them on ebay, but make sure you appropriately mount and cool the regulator appropriately.
It is also fairly easy to get a 12v to 5v 5A regulator, and you could do 1 per appropriate length.
I personally haven’t tried connecting anything straight to a car battery, or its electrical system. But I have had friends who did and they got all kinds of noise, to the point where no matter what size caps were used, they could never get a clean voltage, it just fluctuated too much. This was with a Vicor regulator. Also tried a more traditional LDO with the same result. Ultimately they did the same thing that Arren suggested and that worked perfectly.
I suspect there are ways to smooth it out, after all that’s what every electrical component in a car does. It’s a matter of getting the right circuit built.
I thought about using tablet computer chargers but that would get expensive at $30 a pop. @Brett_Hansen above are some ideas how to power your glow. Perhaps others will chime in
Does anyone how much current one of those cigarette plugs provide? Maybe hack USB charger that you plug into the lighter socket?
Cell phone chargers put out 5v at about 500-700mA Tablet chargers are 5v @ 2000-2100mA. (I work for Verizon and write accessory training among other things).
Is that from AC power, or from a car’s plug-in lighter?
That was vehicle chargers.
Some of the AC cell phone chargers can put out 2-2.1 A.
So let’s see … at 600 pixels, let’s assume full power, that’s 36A. You’re better off with an inverter and getting a computer power supply. A Corsair 650W (CMPSU-650TX) will give you 30A on the 5V rail. Cost $90 @ Newegg.
Unless you are going to light all 600 pixels full white, you may be fine with 30A. If not, there are larger ones. Corsair is just one of the many brands available, I just picked one.
Also, check eBay. Plenty of new ones on there that provide plenty of current on the 5V rail. I saw one a while back that provided 5V/40A and 12V/25A … You just have to search for the right one.
Well I know cars a bit and a regular cig lighter has a 5 amp fuse but it an take up to 10 amps usually or a better India is to run a cig lighter with bigger wire straight off the battery with a 10 gauge how can I hack a USB charger??
Don’t forget that Amps change as a function of voltage, so 12v @ 10A translates to about 5v @ 20A (Assume about 10-20% loss). So you could get close on a standard cigarette lighter. With the higher amperage though, running a separate fused line will likely be your best option.
I use the lm2596 DC DC converter (buck) boards to convert the voltage on my RC batteries to run 5v LEDs. Anyone know of a high current buck board?
For testing I can use a PC power supply correct?
Yes, as long as whatever rail you’re using has enough current for your needs. You have the 3.3V, 5V, and 12V (we’re ignoring the -12V and 5VSB for obvious reasons.) So check the label on the PSU for each rail’s current.
Ok cool thanks