Question about the LED tutorial here

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tbrantb
 
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Question about the LED tutorial here

Post by tbrantb »

I have a question about the last couple questions in the Adjusting brightness section of the "All about LEDs" tutorial

"How much current is flowing through the LED if when the pot is turned down? The forward voltage of the LEDs are 2.2V."

The tuturial says the answer is:
2.2V / 100 ohm = 22 milliamps.

Shouldn't the answer be:
(5V - 2.2V) / 100 ohm = 28 milliamps ???

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adafruit_support_mike
 
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Re: Question about the LED tutorial here

Post by adafruit_support_mike »

Yep.. good catch.

In Tyler's defense, I make that same mistake All. The. Time. ;-)

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