LEDBrick Project - DIY pendant w/ pucks

[theatrus]

I made a mockup for a 4-channel Luxeon Z design which is dense. I'm going to spin one with far less emitters.

New this time:
- All Luxeon Z, 16 emitters, in a 5,4,4,3 channel arrangement
- 4 channels
- Pass-through channels (in one side, out the other)
- 2x wide T-slot (and 1x wide, but the screw head will hit the reflector, left anyway) #4 mounting holes
- Long solder pads to lay wire on if you don't want to use the push-in terminal block

 

[Fredfish]

How are you going to get the LuxeonZs mounted? My understanding is that they are tiny compared to standard 3w emitters.

 

[theatrus]

Low volume: stencil, paste, tweezers, reflow. They are absolutely tiny. But no tinier than fine pitch QFNs or similar

 

[zachts]

Do you have enough leg area for cooling. The Luxeon Z uses the position e and negative leads coped to export heat. Most pc's I've seen use more space to wick awAy the heat.

 

[theatrus]

I haven't put any of the copper pours down for the interconnects. Its not an ideal cooling arrangement by any means. It can be somewhat mitigated by a 2oz copper board, but still...

I may build one for thermal measurements anyway, just to see how viable it is. A lower density emitter combo would be a lot easier.

 

[theatrus]

And a view of the 4 channel 6-up (RB RB B, White, Cyan, Lime) model. XP/XT footprint for the Blue and White, Square footprint for the Royals, Rebels for Cyan/Lime

 

[rott]

I m going to follow this thread also great looking start

 

[zachts]

I haven't put any of the copper pours down for the interconnects. Its not an ideal cooling arrangement by any means. It can be somewhat mitigated by a 2oz copper board, but still...

I may build one for thermal measurements anyway, just to see how viable it is. A lower density emitter combo would be a lot easier.

Yeah rapid led had a huge Luzon Zarray offered for a while. It I suspect it vanished due to thermal issues. The Z is great in tight line arrays but tough to cool in dense grids. A few less, maybe 8 or ten in the same foot print perhaps. Great for 4 or 5 channels in a 20 mill star footprint though!

 

[theatrus]

A two channel setup of Luxeon Zs would probably fare better as you can pull the cathode pours over a much larger area. As you said, a straight line array.

Also, with more emitters drive strengths should be lower (trading up front cost for higher efficiency if thermals are ok). Most people don't seem to optimize for that however

 

[theatrus]

The aforementioned RapidLED Luxeon Z:

Not much surface area for each emitter - I can see where the problems stem.

I think a two channel, 12-up would be possible, with a radial fanout of copper pours for each LED.

 

[Fredfish]

:bounce1::bounce3::bounce1::bounce3::bounce1::bounce3::bounce1::bounce3:

WANT!

And a view of the 4 channel 6-up (RB RB B, White, Cyan, Lime) model. XP/XT footprint for the Blue and White, Square footprint for the Royals, Rebels for Cyan/Lime

 

[Fredfish]

... The Z is great in tight line arrays but tough to cool in dense grids...

I'm rather surprised that the Z has not shown up anywhere in this hobby. I would think this emitter would be ideal for a line array.

 

[theatrus]

:bounce1::bounce3::bounce1::bounce3::bounce1::bounce3::bounce1::bounce3:



WANT!

I'll do some mechanical fit tests (or put up a 1:1 PDF if you want to give it a try by printing it). When I do order some prototype panels there are always more than I know what to do with, so happy to share the prototypes at cost

 

[Fredfish]

I'd be glad to share in the costs for the privilege of playing with my dream LED config.

I don't have a clue how to mount emitters on a board though. Maybe someplace like Steve's would do something like this?

 

[theatrus]

More than happy to mount emitters.

 

[Fredfish]

Thanks.

 

[zachts]

I'm rather surprised that the Z has not shown up anywhere in this hobby. I would think this emitter would be ideal for a line array.

I'm a bit surprised as well as the light distribution patter is excellent as well and the color uniformity from the white emmiters is much better than with the other "dome" lens packages out there.

It would be quite easy to do "multi-channel" clustered line arrays using these little guys as long as you keep it relatively simple and in groups of 4 for good heat distribution. Blue, Royal Blue, Violet, and a nice high CRI white would be more than adequate for the vast majority of reefers tank lighting needs.

I'm also a little surprised that Steve's LEDs doesn't use these yet, though I have heard them mention that they are a PITA to work with because they are so darn tiny.....

 

[Fredfish]

...

I'm also a little surprised that Steve's LEDs doesn't use these yet, though I have heard them mention that they are a PITA to work with because they are so darn tiny.....

I wonder if they are a pita even for pick and place machines.I don't know anything about how Steve's is set up and what capabilities they have.

 

[theatrus]

If a pick and place can't reliably put down a two terminal device of that size it's broken The mainstay of capacitors and resistors are a lot smaller (0402 and under).

The pickup nozzles should also not have any issues due to the flat surface. They'd actually need better pickup performance for a domed package, and pickup performance isn't usually fixed by low end vision systems (which find the center of the part after the nozzle grabbed it).

I have no idea what volume Steve's runs or what their setup is. Low end Chinese PNPs with vision finally cracked the $10k barrier, and a name brand domestic unit (which may not be any better) is easily 3-4x that. If you have the space, ancient Juki machines are still a good bet if you don't mind copying the placement data to a floppy disk and using some DOS software for the setup. Still worth a lot of cash if they come with feeders

 

[zachts]

I wonder if they are a pita even for pick and place machines.I don't know anything about how Steve's is set up and what capabilities they have.

I think Steve's sets the Z BY HAND probably doesnt have the right setup for them. Only on special order and you have to send them the diodes.