How-To: Add 7135 chips to a Driver Board (Stacking)

Hi MRsDNF, you’re welcome, glad to help.
:stuck_out_tongue:
Soldering these little bits does take some practice, and I have had almost two decades of it. Do not be discouraged, keep at it.
Besides, $13 gets you 100 of these chips to practice with :wink:

Thanks relic! You make it look so easy! Then you get these things on front of you and they are TINY! I've not yet got around to trying it myself, but I expect to butcher a few trying!

-Garry

Thanks for the tips between TomE, OL and you I had some successs i tried stacking two chips on a 2.8a driver and one was successful getting 3.15a now. Now just to get the other chip working. Also performed 2 xml dedomes this weekend. Installed the chip added driver and a dedomed xml in a UF-T20 and got 78k and the tint is pretty sweet also. It blows any of my other XML lights away! Now just need to get reflowing down (have had some success with non sinkpads) with sinkpads and then it will be time to hopefully bust into the 100k thrower range!!!

Thanks for the write up

great write up! I had a lot more success when I bent the legs down with a pair of tweezers (a little bit away from the body though). It also worked more easily when I lightly tinned the legs on the chip I was adding too - just a light touch so it didn’t get too much heat.

One thing for those struggling with the tiny bits - if you clamp the new chip on top of the one you’re adding it to with a crocodile clip, then do the back tab as shown above, you can then just use a piece of solid core wire to bridge the pins. Only strip the insulation off the end (enough to bridge the 2 pins) and hold it with a pair of tweezers, then cut off the excess with a pair of nail clippers. It won’t be as pretty as relic’s work, but it’ll function just fine.

Great job Relic! Even if you know how to solder, you can always learn something from others around here. Thanks!

Yep. Thanks again. I think I would end up in the looney bin.

My setup is nearly identical to relic 38's and I still need glasses with that big magnifying glass. My biggest problem is trying to get in to the little tabs with everything next to them if that makes sense. No Room.

I was just sorting through a new batch of drivers I got in the mail. Those chips seem to be getting smaller since relic posted this thread.

I have a disadvantage that gives me an advantage when soldering. I’m nearsighted, and if I take off my glasses I can see things close enough to not need the magnifying glass. I use it after the job to inspect the joints.

I’m also quite nearsighted and do the same thing, who needs a magnifying glass when you can see close-up from several inches away! :slight_smile:

But, while I haven’t tried this yet (am about to which is how I found this thread) I still see problems like MRsDNF described…soldering iron is like getting a tire iron in a pin hole! Perhaps I need to look at getting a smaller iron tip for this type of stuff. I only recently discovered the small soldering wire that makes a huge difference, had always tried the big stuff with lead in it from days of old and always made a sloppy joint. So now that I have learned to reflow an emitter and have been making nicer solder joints I have a new driver coming in at 3.04A and wish to add a few 7135’s to bring it up to around 4-4.5A for my HD2010 with it’s new copper star and XM-L2 emitter.

Thanks for showing these pics, makes it less scary and I’m ready to attempt adding 4 of these. Where do you recommend I purchase em? The new driver is already on the way and I’d hate to wait 2 weeks for some of these tiny things!

I have experienced flickering but seemed random. Once it starts flickering I could not seem to find any pattern to the flickering. All the connections where good. This could possible explain why the flickering occurs. My flickering only seems to occur in low mode. It doesn’t happen that often but I have experienced it in a couple of mods. I always thought maybe one amc7135 got to hot so I would replace the added chips. Sometimes the flickering went away sometimes it didn’t. If it didn’t I just started all over again with a new board.
Has anyone else here experienced flickering when they bent the pins down before soldering? Relic38, have you experienced the flickering personally with bent pins?

I have not bent the pins before. My issues with flickering were mostly clicky or driver contact issues.
I can see how a weakened bond wire could produce flickering in different modes. Heat in a high mode could provide reasonable contact due to expansion. Once you switch to low, the contact could spread and weaken the contact. I suppose it could work in the opposite manner too. Stressing a tiny thing like what is inside the 7135 chip (picture a grainor two of sand) is why I avoid bending pins.

That seems to be when the flickering I noticed starts after I have used high for good amount of time. After that it may only take seconds for it to start flickering even after the light has been off for some time. The flickering did not start until the extended run in high mode. I may go back to soldering without bending the pins for awhile and see if the problem goes away.

I figured I better get prepared. I only have the tip that came with my Weller WESD51, so I ordered something a little slimmer. It may be of no use at all, but maybe it will help.

I have narrow and wide tips; I prefer the widest tip that I can fit for the job. Thin tips have a heat transfer issue and do not work well on pins and pads that conduct a lot of heat away. For that reason, I almost always use a ‘stumpy’ 1mm x 0.5mm tip (I forget the exact dimensions). I solder 20 pin surface mount chips with 0.030 pin spacing with it. I have more trouble doing the same with a smaller tip.

Does the fatter tip help pull the “blob” up to the top pin easier?
What jobs would the finer tip be best for?

Awesome guide!

I’m thinking of giving it a try.

I just built my first multi-emitter might. It’s a modded Sipik 58 running on 1x14500 IMR with triple Nichia 219 and 3.04 amp Nanjg 105c driver.

There’s room inside to add another row of 7135s on the top of the driver and I have the chips on hand. I could increase the current to 4.5 amps.

Heat and short battery life might be an issue in such a small light though. I added a copper heatsink behind the star, but it’s not very big. I’m also not sure if raising the current to 4.5 amps is really worth it. Doing so would increase the theoretical output before optics from 266 lumens per emitter to 336. Assuming 30% loss due to optics and other inefficiency and output would rise from around 560 lumens to 700… at the cost of drawing 50% more power.

Ah, shame you didn’t get the 219’s binned for 475 lumen output at 1.5A. They you’d have some serious output on that triple if you stacked the chips, be worth the effort for sure!

I have one of those reflowed to a copper star and side by side it outputs very similar to an XP-G2 (which is claimed 520 lumens @ 1.5A) the 219 has a visbily smaller hot spot due to a slightly narrower angle so it might give a better throw with a triple configuration.

Just ordered 20 of the AMC7135’s binned at 380mA to match the ones on the 3.04A driver I’ll be modding. Each step is exciting as I learn new things, hope I can pull this one off! :slight_smile:

Interesting.

Actually, I don’t really know what the output is on my 219s. I looked up a table in a Google search that showed 266 lumens at 1 amp and 336 at 1.5 amps. I purchased my 219s at Illumination Supply.

Any idea where to buy 475 lumen 219s? I assume they’re still high CRI.

As I didn’t want the 4500K versions and preferred a bit cooler tint, I went with the 5000K version with more output. I found them here: http://www.ledrise.com/product_info.php?info=p1499_Nichia-LED-Series-219-NVSW219A-475lm-Emitter-White.html.

Mistakes I see that are quite good help when doing this:

  1. flux, use the damn flux!
  2. bend the legs of the 7135s
  3. do solder all pins the middle one as well
  4. most people do not have holding hands

I place the driver in big pliers that have a rubber band over them. Holds the board.
Bend all 3 legs down.
Flux all connections.
Hold with something, like a clothes pin or glue, the new 7135 in place.
Solder one by one, probably do the tab first.

A very thin soldering tip proved bad for me, it just did not have the power as it was too long. That is with a 50W temperature regulated soldering iron, even boosted the damn thing up +30°C but it’s still pain in the neck to solder with the longer tip.
Just use a normal soldering tip, works for everything for me.