Mixing and Matching types of led's

[Christoph]

Hi friends
I am making a foray into the fixed lighting world (I have so many extra leds at the moment) and I plan to use the [FONT=Arial, Helvetica, sans-serif]Xitanium drivers. My question is I plan to mix some old lux low domes and some cree q5's in the same string. Now I remember that a series circuit will have the same current flowing through the entire circuit how important is the relationship of the vf between the individual devices. Will each piece just drop the voltage it needs to achieve the output current? Do I need to put them in any special order? I am hopeing thet this will work because I like the color mix I get with the lux and cree mix.I have yet to work out the diffusing method.
Thanks in advance
Chris😀
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[LukeA]

You can do that and it will work fine.

 

[blasterman]

Like LukeA said, should be no problem. I mix radical Vf values on the same string all the time with both regulated and non regulated supplies.

It's when you mix parallel strings with different cumulative Vf's that can get you into trouble with constant current supplies.

 

[Lynx_Arc]

just make sure that the LEDs with the lowest Vf that can handle the least power are not overdriven too hard.

 

[jeffosborne]

Those old Lux low-dome LEDs you mentioned, if they are Luxeon-I then they are rated for no more than 350ma - 'absolute maximum rating' they call it. Of course over-driving is a rather common practice around here, but it can shorten the life span and mess with the tint, too. What is your target current for the lights? Cheers, Jeff O.

 

[Christoph]

I am just going to drive them at 350ma I will get some pics when I get a chance.I got these a few years ago and back then we were DD'ing them pretty high in some lights I seem to recall some of my lights seeing almost an amp for a short while.
Chris