I have a project where I’m using some 12 volt LED strip lighting.
I’m wondering if I can power 0.45m of it from the GPIO/5v pins?
Do you think that its possible to use this:
to boost the voltage from 5v to 12v to power the LED strip (the strips take about 900mA per/meter)?
The pi typically is only powered by a 10-12 watt power supply. Not enough to drive the LED strip lights. Get a beefy 12V supply to drive the LED strips directly, and a buck converter attached to that supply to provide the 5V for the pi. It may help to put a large capacitor across the output of the buck converter to remove ripple/noise.
The pi’s GPIO pins can only source about 50mA max, but that’s enough for driving the logic circuit of the strip lights.
I’ll try it!!
With respect to the Pololu devices. I have used a number of different types and are very happy with their performance. But getting 12V from 2 x AA cells results in not much current before the voltage regulation drops. Using 4 x AA cells to produce 5V works really well. Stable 5V supply as battery voltage varies.
If you need 12V, try for a battery supply close to 12V, ie 6 or 8 x AAs. Stepping voltage up, steps current down.
Level conversion may be another issue, depending on the type of Led strip you have. If it is programmable, connecting 5V logic to a 12V device may damage either device. I have used a level converter provided by Core Electronics (SparkFun device) to convert 5V to 3V very successfully. This device maybe able to convert from 5V to 12v; its just Mosfets. Dont know for sure.
As Robin57159 stated, GPIO pins on micros are not designed to provide high current. I have used a GPIO to drive one or two Leds, but always make sure the current is within specification. (usually less than 20mA).
the strips are not programmable so I ended up trying what Robin57159 stated using a 12 volt supply and buck converter to convert the 12 volt to 5 volt and powering the strips straight from the 12 volt supply.
Good to hear.
I used a Pololu 12V Step up regulator; to step up the voltage from 4 x AA cells to power a strip of 18 LEDs.
Its a kind of portable light, I have used it for light painting photography.
Works well and lasts a few hours using rechargable NiMh cells.