One Driver..Two Diodes?

[wolfblue]

Is it really ok to drive two diodes with one driver? Or is it like a last resort if you cant afford another driver.

I've heard parallel with the two 1R's is better. But how often do diodes fail open?

And, I've heard series is the better way. But then you need more than 5v for red.(Flexmod)

What do you think?

--John

[MechEng3]

I have 4 LOC diodes that are on one driver doing well no problem. This is a project of 2 lasers under final construction. Pix to share when they are finished. Yes it will work fine.....just look up DrLava's post titled "Super Red" in the search field......

[Psi]

The voltage vs output power of diodes isn't exactly the same, even between diodes that were produced in the same batch.

Depending on which diode you get the voltage to output power value from you'll end up driving the other diodes at either more or less output than you wanted.

The more diodes the worse it gets, as you have to drive all the diodes at the voltage that the most sensitive diode outputs full power at or you'll over drive it. (and the other diodes wont run at full power at that voltage.)

It's not much of a problem tho, unless your diodes are very low power where small changes in current effect brightness a lot.

[drlava]

That's why you should put a 4 ohm 1/2W resistor (for red) in series with each diode for load balancing, as in the thread MechEng pointed out.