Arduino UNO: max current on Vin pin?
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I am going to build a LED dimmer shield for the uno. My LED strip can consume up to 6A. Can I connect the shield to the Vin pin and take the 6A from there or will this break my arduino? I did not find this info in the specs.
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The Vin is a input, not an output. You have to provide power into Vin, instead suck power from there.
You need a good 6A powersupply, and you can share it between arduino and the LEDs.
Arduino outputs can drive a maximum of 40mA , so they will immediately fry in case you connect your 6A LED directly into it. You need an Power transistor in between to drive the load.
I may want to check the http://www.mysensors.org/build/dimmer , it should help you too.
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From the official Arduino website: "VIN. The input voltage to the Arduino board when it's using an external power source (as opposed to 5 volts from the USB connection or other regulated power source). You can supply voltage through this pin, or, if supplying voltage via the power jack, access it through this pin."
The does not seem to be true.
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You can access it through this pin, however this pin presents the output from the small voltage regulator onboard. It can supply just few milliamps. It is okay to connect some low-power device to the Vin (something up to 30mA, such as temp or motion sensor).
A 6A LED strip connected to Vin definitely won't work (unless you want to produce some smoke / fireworks ;-) )
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Vin is not the output of the voltage regulator but its input. I just need to know the specification for this pin. I had a look at it and there is nothing but the trace on the pcb between the input jack and the Vin pin.
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It can only supply few miliamps, nothing more than that. It is more used as an input if you want to use a external voltage regulator (bypassing the one onboard).
I doubt it can supply more than 100mA.
From the arduino website:
VIN. The input voltage to the Arduino board when it's using an external power source (as opposed to 5 volts from the USB connection or other regulated power source). You can supply voltage through this pin, or, if supplying voltage via the power jack, access it through this pin.
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Ok, as it seems I did not look good enough. There is an diode (smd M7) between the input jack and the vin pin. This diode is rated 1A. So this will be the maximum current available to the whole arduino + shield. I will put a jack on my shield and feed the arduino from the shield and not vice versa.
