stupid led question

[pinkjimiphoton]

hey guys, need a little advice here... when using multi color led's,  if you want to have two of them connected is it better to connect them in series, or in parallel?

also, do you use a larger current limiting resistor, smaller, or the same? does it depend on whether the led's are in series or parallel when
choosing a better method?

i wanna be able to run two pairs of led indicators, one side two blue, one side two green.
i'd KINDA like to have both sides, or at least whichever side is active in the circuit at the time turn red in bypass mode.

i'm pretty sure i know how to do that for one pair... simply connect the red lead to the unused lug on a 3pdt with the center being ground if using a common anode tricolor led.

but unsure of how the best way to supply this would be as per the initial questions asked above.  advice always gratefully sought.

[EBK]

Trying to understand what you want.  Does this seem right?

Both sides bypassed:
R R    R R

Left on, right bypassed:
B B     R R
Right on, left bypassed:
R R     G G

Both on:
B B    G G

[antonis]

Trying to understand what you want.  Does this seem right?

Both sides bypassed:
R R    R R

Left on, right bypassed:
B B     R R
Right on, left bypassed:
R R     G G

Both on:
B B    G G

Now I'm trying to understand what you say...!!! 

@Jim: Do you want the pair of bi-colour LEDs for more brightness or for individually seperate indicators..??

[TejfolvonDanone]

If you connect them in series:
1) both LEDs get the same current (the brightness will be similar)
2) you only need 1 resistor
3) you might run out of supply if there are too many in series or with too high forward drop
4) the resistor should be smaller because the 2 LEDs dorp is higher
If you connect them in parallel:
1) You need 1 resistor in series with each LED (else one might not turn on because of the forward drop difference)
2) The current (brightness) can be individually tuned by the resistors

But i think most multi colour LEDs have common cathode or common anode so the different colours have to be in parallel. If you need to switch the different LEDs from the same multi colour LED i think it is much easier if you connect all of the in parallel. With the common anode/cathode you are not able to connect only the same colour LEDs in series thus if you change the colour of one of the LEDs the brightness will change.

Now I'm trying to understand what you say...!!! 

2 LEDs for 2 sides of the pedal. BUT: now off is indicated as red and on as green for one side blue for the other.

But i'm not sure what Jim tries to do. 

[antonis]

Shouldn't be easier (and simpler) to have NO colour on Off/Bypass...

[TejfolvonDanone]

Shouldn't be easier (and simpler) to have NO colour on Off/Bypass...

With a regular 3pdt switch and a bicolour LED it's not really a big deal

[pinkjimiphoton]

thanks guys for the information and answers, and i agree with a 3pdt it's no big deal.... easy breezy.

use a common anode, one resistor, choose your colors... with a three color you can choose two. put your ground to the common
pole, and one color on one side, one on the other. stomp the switch, changes from one color to the other with whatever else you're doing.

but in this case, i'm considering a bunch of different possibilities and most of it is just cosmetic.

i need two pairs of led's to light up at a time. think of them as "eyes" in a graphic. hit the switch one way, two led's light up blue, hit it the other way, two led's light up green.  that part is fairly easy, and it appears a series connection should be fine... one resistor per pair, thank you all for confirming that.

what i'd like to do, and this is where it gets tricky for me and probably isn't worth doing, is have all 4 "eyes" turn red when the effect is bypassed. just cuz i think it would look cool, and running 5 led's off a 9volt circuit may be too much if i want an on/off indicator. two on each side for the "effect" a or b, and one for bypass/on

but to me, the obvious way to do it is to keep the three things separate.

but then it occurred to me that maybe i could use the unused pin on the bypass switch (two stomp switches) to ground the red cathode on a tri color if i used them for the eyes...  i may have to draw up a bad graphic to explain this better...  but it should work i think.

but i wasn't sure if diodes worked like caps or resistors where there is a resistance or impedance to them that must be considered.

let me draw up a circuit real quick and post, maybe my ramblings will be easier to follow.

one switch is pretty much standard 3pdt. the other will be a 4pdt if i add the led's as planned, as i am already using all three switches to swap components in the circuit.

gimme a couple minutes guys, and again, thank you all. 

[EBK]

I'm thinking this:


Or, the two independent stomp version:

[pinkjimiphoton]

thanks bro, but it's gonna be more like this kinda...

except i was too lame to do it right, so i condensed it to just one led. in reality, there would be two pairs. just the green cathodes of one pair  on one side to the top of the switch, both the blue cathodes from the other pair to the bottom of the switch, both red cathodes from the two pairs of leds to the bottom pole (normally unused) of the effect bypass switch.

this way when it's off, all four leds will glow red. when you turn the effect on, the red dissappears and is replaced by one pair of blue "eyes" or one pair of green "eyes"...... with me now? sure seems it should work.

so that way, one resistor per pair of led's in parallel two switches and dumb useless but kinda cool visual effect for one box that lets ya choose between two different but related fuzz circuits..... what do ya think?



i hope the graphic doesn't make it more confusing, i realized after i drew it up i shoulda made at least two leds in it instead of one, but i think i got it figured out and hope you can too

[EBK]

I think I see it now:
At any particular time, the pedal is either bypassed completely OR one of the two circuits (blue or green) is on, but not both, right?
So, three LED combinations:

R R R R (bypassed)

- - G G (right side on)

B B - - (left side on)

[pinkjimiphoton]

yep, exactly.

i've been trying to post another graphic, but @#$%in photobucket spams ya with so much bullshit these days i can't access a goddamn link to post it.


http://s605.photobucket.com/user/pinkjimiphoton/media/stupid%203%20color%20led%20trick%204%20leds_zpszzmsw3cu.png.html

seriously time to stop using photobucket... 666 scripts, 46 different ads.... takes more than 5 minutes just to LOAD all that bullshit!!



i had to right click, "view source" and then copy the @#$%ing url!! what a joke!! i have literally been trying to get the goddamn url for this stupid graphic since i posted the initial one... man, what a SUCK service!

[EBK]

I'd recommend a separate CLR for each RGB led (so, 4 total instead of 2).  If you put 2 LEDs directly in parallel, with one CLR shared, any slight difference in Vf may become apparent as either a difference in brightness or only one LED actually lighting.

[pinkjimiphoton]

perfect, thanks erik, that makes sense bro.
exactly what i wanted and needed to know...
i'll post some pics when it's done finally, it should be kinda cool.
the circuit is cool as hell, but the blinky blinky's will make it LOOK cool, too.
thanks!!

[bluebunny]

1. to avoid the two-LEDs-in parallel, fight ensues, one LED wins scenario, put them in series
2. imgur.com 

[pinkjimiphoton]

ok, but how the hell do i put two rgb led's in series?

i don't see how i can do that and accomplish what i'm looking to do, or maybe i'm brain dead.

series is hard with a common anode. shit, pretty much impossible i'd think bro

i could see it being done if i used two leds of each color on one side that way, but no way to make it red when in bypass. thanks tho!

imgur i will check out. i've about had it with photobucket

[bluebunny]

Hmmm...  You're right!  Now you say it out loud, I can feel the ol' grey cells start to overheat...     (I suppose it might be slightly less brain-melting if you managed to find a pair where one is common-anode and one is common-cathode.)

[pinkjimiphoton]

so in all seriousness you're telling me i need to place ANOTHER parts order?


the wife is gonna LOVE BOTH of us for that... 

methinks me will stay with the original plan !!!

thanks bro!!
but if i order one more thing, it better be a hammond 1590zzzz cuz i'll be living in it!!

[EBK]

(I suppose it might be slightly less brain-melting if you managed to find a pair where one is common-anode and one is common-cathode.)

No, that would be just as brain-melting.  Go ahead and try to sketch it out. 

[pinkjimiphoton]

far out, i breadboarded them in series, like, right???   

with some nice RGB 5mm led's, right?

thanks man, now i have a litter of 37 3mm clear led's.   



ok, GONG!!!!





fail'd at comedy

[Cozybuilder]

This could be done with 2 RGB LEDs, 3 resistors and the two 3PDT stomp-switches (pedal on/off, and effect select). Adjust the CLRs to give approximately the same brightness of each color:



Edit:
On second thought, you would need parallel orientation due to the common cathode, so the switched ground drawn above should be +9V, with the resistors connected to the parallel LEDS. Adjust the resistor values so the individual LEDs are of equivalent brightness. Like this: