I'm not quite a beginner, have worked my way through more than half of McWorters tutorials but I'm having a problem with the simplist circuit with an uno, a 220 ohm resistor and an LED. I have the 5v pin hooked to one leg of the resistor, the other leg of the resistor hooked to the anode, and the cathode hooked to ground. There is no sketch and everytime I run it the LED blows and it says there is 435mA rather than the 20 max. How can that be. Where is the excess coming from. Has Ohm forsaken me???
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But in Tinkercad to get 435 mA from a resistor and LED beteeen 5v and gnd the resistor needs to be 670 mOhms in my TCad circuit.
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Just doing a quick calculation it sounds like your 220ohm resistor is actually 2.2ohm. Might want to verify that.
Good luck.
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Like this?
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Ok. In tinkercad. I did what you said.see if this is it. The resistor color code looks right. But the resistance is set to mOhms.
If you are in kOhms, put in 220 then change works. The resistor changes to set Value, Then change multiplier to mOhms then the color code don't change to mOhms - the resistor bands don't change. So you cant see if you set it wrong. Must be a bug. Getting to it other ways the value and color code change.
Anyway, change it to just Ohms. Or 0.22 kOhms
I put in a bug report.
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did you miss a decimal point, is it red-red-brown? #virtualworldproblems
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I left out the most vital part, I am doing this with Tinkercad, which I have spent quite a bit of time on.
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I found it. I had a direct short. I thought it was a board with 2 separate legs on the + and - strip, so I had 5v, both legs of 220 and leg of LED plugged into the + strip. DuH. Learning is an adventure.
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make the circuit public let me know the circuit name & I will look at it. No guarantee to solve though.
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