I am working on a project with the arduino uno r4 wifi and i need to know how much current i can draw from the 5v pin. i need to run 16 standard neopixels that will each draw around 60ma each. i would like to know the current of the pin while powered from the VIN, barrel jack, and usb-c separately.
The datasheet will tell you. It is under Arduino.cc/Hardware I think it's only 10ma
The pin current has nothing to do with the power source.
Yes, but that's not the 5V output pin. The capabilities of that, as near as I can tell on Arduino.cc, are very vague. Pity. The USB power will, of course, be limited by the supplying computer or USB hub, or whatever.
Worth reading:
Personally, I'd use a 5V supply direct to the USB connector, but as shown, feed the LEDs separately, rather than drawing their current through the onboard circuitry.
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From the documentation:
When powered via the VIN pin,... the 5 V pin can provide up to 1.2 A.
...
When powered via USB,... the 5 V pin can provide up to 2 A without damaging the board.
However, as already noted, the USB power source may constrain the magnitude of current that can be supplied.
Also, keep in mind that the total current includes the current drawn by the components (MCU, LEDs, etc.) on the board itself.
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is there possibly some kind of power supply shield that would supply power to the arduino vin and power to components
Yes it does, because the voltage regulator will limit the maximum current that can be pulled from the 5V pin when using VIN to power the board.
I think we mean the same, it's 8mA regardless of power source.
NO, you can't use an MCU as a power supply. It's pins are logic level. You will need to use a transistor or MOSFET that the pin will control and the transistor or MOSFET drives the high current devices.
He isn't trying to. Re-read. He's looking for how much current can be drawn from the 5V pin, not an output pin.
As answered in post#7, which is the data I failed to find at Arduino.cc. Well done, @grb !
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@sonofcy i'm not sure you understand. I want to power the neopixels from the 5v pin on the uno not the data pins. what i am asking is if there is some kind of shield or module that would have a barrel connector or usb c connector that would have outputs to power the uno R4 through VIN and seperately power the neopixels
See post #7 - the R4 has enough oomph for what you described.
how many amps would i get when using the barrel jack connector?
My bad I misunderstood.
Drawing 16×60 mA while powering the board components might be iffy if the supply voltage is via VIN, but if using USB-C with a 3-A power supply, I would think they shouldn't have any trouble.
I misread, apologies.
DC barrel jack (J5) is the same as VIN, so no more than 1.2 A (including all of the power consumed by the Arduino board itself).
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I misread and I have a bias, I NEVER use a board to power anything like that. I will leave it to others to tell you if it's ok or not.