Peter Todd wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > On Sat, Jun 23, 2007 at 09:06:29AM -0400, Rolf wrote: > >>>> *** actually, I have 16 RGB LED's, but I have 8 shining up from the >>>> stage, and 8 shining down on to a white-board for cool effects.... There >>>> are 8 light "boxes" and the 2 RGB LEDs in each box are wired in series. >>>> Because the G and B LED's have high forward voltages (4.5V which in >>>> series is 9V, I am driving the LED's at 12V, but the PIC at 5V). >>>> >>>> >>> 12V 'eh? With no resistors, or are you relying on pwm to limit the >>> average current? >>> >>> >>> >> As for releasing the code, I am happy to give it over to you with a GPL >> license. I just don't have the facilities to host it, etc. Perhaps I can >> put up another page on piclist. It will take some time, and if you want >> to get a heads-up I can e-mail it to you sooner. >> > > No rush, I'm trying to avoid too much work on this whole thing until the > art show is done, but I'd be happy to figure out some sort of > "contributed code" page on my site, and a piclist project repository is > a good idea too. > > Hmmm... I spent about 45 minutes looking around Piclist this morning, played with a few things, but (James, are you listening?) I gave up. I simply could not find a button/link/faq to create a new page. I have spent too much time working on other "user modifyable content systems" (mediawiki, and others), but I just can't get my head around how to set up a page. Sucks. >> As for the 12V-with-no-resistor,... no. I have resistors on each LED. I >> am using the RGB LED OVSTRGBBCR8. Each colour has an 80mA maximum >> > > Oh, with the PLCC6 case. How did you find soldering them? > > I gotta admit I haven't considered non-thru hole leds in my price > reasearch yet, looks like the cheapest ones are smd. > > I went with them because they are all that Digikey really offers (in RGB LEDs), initially I would have preferred T-H LED's to simply solder to the end of a wire. Instead I made mini PCB's for each LED (double sided) so that I could put one LED on top, and the other one in series underneath (hence get one light shining up, and another down....). On the other hand, the "motherboard" I intentionally made all SMD. I have been wanting to do it with something less critical than my next project... I need the practice. I managed to get it all as a single-sided PCB, and used the photo-resist route with a toaster-oven reflow solder. It was all so much simpler than I had thought it would be. I had checked out a lot of "how-to" places on the process, and I figured I would screw it up somehow, but it came out close to perfect (I had 2 1206 sized resistors slide sideways and bridge a trace.... easy to fix and moved on. Took me about 1 hour to prepare about 90 smt parts, and 20 minutes to check that I got everything in place. Then another 20 minutes with solder paste, and finally, 5 minutes in the oven. 20 minutes of checking each trace and discovering the skew resistors, and I was done (with the SMD parts). Then I had to spend hours and hours cutting crimping cables to feed to all the 'remote' parts like the LED's and the buttons and knobs.... I am planning on putting together a 'package' for James so that I can contribute it to the Calendar .... I was very surprised, and also very chuffed/proud that 'it just worked'. As for the RGB LED's, based on your pricing of other things, I probably should have looked elsewhere for them since they were $4 or something each - I used 16.... >> continuous rating. I did my math at 50mA. The G and B have 60Ohm, the R >> has 140Ohm.... with 4.5V drop, to limit current to 50mA on the G and B >> (and having 2 LED's in series), I have a 9V drop on the LED's, and the >> 3V/60 gives 50mA. With the red, 2.5V forward, that leaves 7V to control >> current, I am using 140Ohm. >> > > Good choice on the 50ma, it'll run 'till you're daughter's an electrical > engineer and wants to upgrade it. :) > For the record, the RED LED's are not as bright as the G and B LEDs at 50mA. I am going to have to go at some point and de-solder/re-solder the Red LED's resistors, and bump up the current somewhat. I expect I will have to get them closer to 80mA to get them the same sort of brightness as the others. > - -- > http://petertodd.org > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v1.4.1 (GNU/Linux) > > iD8DBQFGfd5o3bMhDbI9xWQRAurmAJ0RoBUtZH3zLo0iOtuMQLVWagFQhQCgrq5v > ytPO/UFSiA/uFGfMZt1Lycg= > =AS0Z > -----END PGP SIGNATURE----- > Rolf -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist