ok, thank you! I'm definitely a hardware newbie, so I am easily confused 
:-) 

On Monday, January 13, 2014 11:52:15 AM UTC-5, Gerald wrote:
>
> These are low current very bright LEDs. I had to increase the value in 
> order to dim them because people were complaining they were too bright. The 
> power LED, that is also the same value, 4.75K, not 820 ohms.. Check the 
> latest schematic. The transistor has some voltage drop in it, so even at 
> 5V, the LED brightness is about the same.
>
> Gerald
>
>
> On Mon, Jan 13, 2014 at 10:43 AM, <[email protected] <javascript:>> wrote:
>
>> I'm confused about the resistor values used on the user LEDs on the BBB. 
>> The first question is, the power LED (D1) is on a 3v3 circuit. The 
>> datasheet for that LED says the fwd voltage is around 3V @ 20mA. No matter 
>> how I spin it, i can't figure out how in the world they came up with an 820 
>> ohm resistor??  (3.3 - 3.0) = (0.020)(R)..     ? 
>>
>> The second question is, the USER LEDs (D2. D3. D4. D5) are on a 5V 
>> circuit. Yet guess what, they still somehow figured on an 820 ohm 
>> resistor??    So confused.. 
>>
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>

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