GPIO on the Raspberry


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by jped » Thu Jun 27, 2013 4:16 pm
How many mAh does the 3.3v on the raspberry pi output? How much do the logic pins output?
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by RaTTuS » Thu Jun 27, 2013 4:22 pm
http://elinux.org/RPi_Low-level_periphe ... .28GPIO.29
but basically don't try and power stuff via the GPio [some stuff works - low level LED]...
http://www.catb.org/esr/faqs/smart-questions.html <- ask smart Questions
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by alexeames » Thu Jun 27, 2013 5:00 pm
jped wrote:How many mAh does the 3.3v on the raspberry pi output? How much do the logic pins output?


~16 mA Max for one pin, but no more than ~60 mA for the whole lot (from memory) as Rattus says, though, best tap the 5V line or use another source if you can.
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by solar3000 » Thu Jun 27, 2013 6:19 pm
Yeah, like they said, 50mA max from the pins marked 3.3v.
But 50mA would be the max for all pins added together.

So if you suck out 25ma from pin 17 and 25ma from pin 1, you'd just maxed out. (I'm not 100% sure though) I saw the schematic once, I don't remember if they were wired together or not.
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by alexeames » Fri Jun 28, 2013 7:22 am
solar3000 wrote:Yeah, like they said, 50mA max from the pins marked 3.3v.
But 50mA would be the max for all pins added together.

So if you suck out 25ma from pin 17 and 25ma from pin 1, you'd just maxed out. (I'm not 100% sure though) I saw the schematic once, I don't remember if they were wired together or not.


You're not supposed to take more than 16 mA from one pin
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by pluggy » Fri Jun 28, 2013 8:08 am
You could get as many mAh as you want out of the Pi's GPIO - eventually. Somebody doesn't understand the difference between work and power. But then again half of those who earn their living from the energy industry don't either.......
Don't judge Linux by the Pi.......
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by alexeames » Fri Jun 28, 2013 8:26 am
pluggy wrote:You could get as many mAh as you want out of the Pi's GPIO - eventually. Somebody doesn't understand the difference between work and power. But then again half of those who earn their living from the energy industry don't either.......


And the rest of us answered the intent behind the question. :lol:

You are, of course, absolutely right though.
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by pluggy » Fri Jun 28, 2013 8:46 am
Pedants don't see the intent behind the question. :)
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