Another LED question

[Bounty]

First of all I want to thank you for helping me with my previous LED problem. It works like a charm

I have 3x 27ohm resistors left unused from last thing i 'built'. The questions is can I use these 3x resistors for another project?
I would like to use only two blue LED diodes on any source.
Can I somehow make a circuit that includes 2x blue LED diodes and up to 3x 27ohm resistors? Or maybe 3x diodes or anything similar..

I tried calculating the values on the LED circuit calculators but I couldn't find anything to do with these three resistors.

Thanks again.

 

[Harald Kapp]

The idea of finding a circuit just for using up available components sounds a bit unconventional.

I would like to use only two blue LED diodes on any source

This won't work. Your choices of source are limited by the components at hand.


Here's one example how you can use your components:

(Note: NSPW500S is only a placeholder for your LEDs)
Each LED drops approx. 4V. Let's assume a current of 10mA throught each LED.
10mA will drop 0.27V on each of R1 and R2. Current through R3 will be 2*10mA, therefore voltage drop across R3 is 0.54V.
The total voltage across R3-R1-D1 (or R3-R2-D2, which is the same) will be
4V (D1)+0.27V (R1)+0.54V (R3) = 4.81V.
Therefore you could operate this circuit comfortably from 5V (e.g. USB power) or from 4.5V-6V with some variation in current.

 

[Bounty]

Thanks,I will try this out as soon as I find time.