I have a line of leds but white and blue dont light up no there not broken

no there not broken i think i need more power but im scared i will brake them? Do i need something or do you need the other colors there's white blue green yellow and red im using AA bateries

sort by: active | newest | oldest
lemonie8 years ago
Circuit diagram / how you've wired these would help us to answer the question (otherwise we are guessing) L
el triste13 (author)  lemonie8 years ago
ok there the two wires and i peeled them then soldered the positive with the + and - withe the- do you need the order the colors in?
Series or parallel? I'm guessing at the top way in this diagram, where you don't have enough power to run white & blue (higher voltage) but there's enough for the rest?

The lower circuit would give the same current through all if you had enough voltage to drive it.

What way are these wired together?

L
led.bmp
el triste13 (author)  lemonie8 years ago
Yeah its the top way and do i need any resistors?
That's your problem there then - blue and white LEDs take more forward volts to light up ! I can't remember exact figures. You WILL destroy your LEDs if you try and increase the volts to get the white LED lit ! Do it like Lemonie shows, but please put a current limiting resistor in series with the supply. If the current each LED needs are significantly different, go back to the parallel circuit, increase the volts, and add a resistor to each LED.
el triste13 (author)  steveastrouk8 years ago
yeah once i burned them but not cause the voltage i made negative and + touch by accidents and i had to star all over but luckily i had 20 of each colors
Wired that way, the LEDs that light offer the easiest path for current, there's not enough power / voltage to run the two that don't. You would be better with a 9V battery and maybe splitting the lower voltage G Y R and WB, like this:

Guessing" the G Y R probably need 1.5-2V and the blue white 2-2.5 V or something - for a guide use this: http://led.linear1.org/led.wiz
Something like 300 ohm for each resistor?

L
9vled.bmp
el triste13 (author)  lemonie8 years ago
thank you very much for the help and if i have another problem ill ask later
mr.origami8 years ago
try a 9v battery that how i got mine working
el triste13 (author)  mr.origami8 years ago
wouldnt that burn them out
codongolev8 years ago
series or parallel? also, white needs the most power. it would make sense that it's not lighting up. I don't know about blue though.