LED Driver - BuckPuck 3021

[Shilood]

I'm sure this has been discussed somewhere, but searching all of LPF I am unable to find any reference to using BuckPucks to drive an LED. Are they not used because of their larger form factor (0.83" square) or is there some other attribute that makes them unsuitable for driving a laser LED?


http://www.leddynamics.com/LuxDrive/datasheets/3021-BuckPuck.pdf

The adjustable versions allow an LED current adjustable between 140ma and 385ma. On the surface that sounds perfect for driving a GB LED.

 

[dynamicvelocity]

These critters supply fixed current variable voltage... which i think is not what lasers want (at least not laser experimenters) - to experiment with LD's i think what we are looking for is a constant (but adjustable) current source, to determine the current at which the diode 'performs best'.

 

[Benm]

A current source is actually fine, and in that respect, these modules should work very well on laser diodes.

However, sometimes the output of such switching led drivers isn't very clean. I would be impossible to tell much about that without testing one of those units with a scope, unless there is a schematic of the internals.

 

[Things]

is it a voltage step-up kid of circuit? if so, the output will be very "messy", so it will need to be rectified(which the laser diode should do, since it is a diode, but i don't know how it will like this)

 

[Zarniwoop]

Hopefully everybody is putting a capacitor across their LD anyway - I'd think that would clean up the output enough, if it's not already built in.
It's a shame they don't have any with a lower minimum voltage to allow for more battery sag before dropping out. In principle though, it's probably very similar to the circuit in a mini Dorcy or any number of other flashlight driver circuits being used with laser diodes.
Does Digi-key sell these? How much are they going for?

 

[Shilood]

http://www.allegromicro.com/en/Products/Part_Numbers/6280/6280.pdf

Interesting choice if you want to use PWM or drive 3 LED's to a max of 150ma each.

 

[Skram0]

A quick google search and here's the first that came up. I'm sure if you went past the first hit you'll find plenty more and possibly cheaper. $26-$33
http://www.theledlight.com/luxeonled_drivers.html

 

[Shilood]

Yes, found em for $18 for the DC variety, $21 for the AC input type. 20mm x 20mm square puck.

The output current is controllable through a small set screw, adjustable from 140ma to 385ma. No external trimmer pot required unless you want to adjust current more than 100 times or so (predicted failure of the pot adjust screw.)

They do sound perfect for building a lab laser if you don't already have a current adjustable power supply laying around. (I'm not suggesting the output is filtered to 0.1% or ripple-free, only that continuous duty is possible with either AC or DC as a power source.) The output can be PW modulated with this module too if you connect a TTL or CMOS microcontroller or timer circuit.