SF Bay Bridge + 25,000 algorithmically controlled LEDs • Hacker News Board

Re: SF Bay Bridge + 25,000 algorithmically controlled LEDs

#31

Post by nathanstitt » Fri, Jan 25, 2013, 4:39 AM UTC

fnordfnordfnord wrote: post #27

nathanstitt wrote: post #13

Does any hardware hackers out there have a source for the large scale switching boards that are at least semi-affordable? I'd like to tinker with switching on/off few hundred leds at a time but haven't found a source for a board yet. Bonus points if it'll power RGB colored ones.

Take a look at Buck Pucks or one of the many similar easy to use drivers whose names escape me at the moment.

Correct me if I'm wrong, but it's my understanding that the Buck Puck is just a single series driver that provides a fixed current.

I want to be able to wire up around 100 leds to a board and then connect the board to serial and/or USB and be able to change the switch on/off and ideally change the RGB of any of the leds independently.

Re: SF Bay Bridge + 25,000 algorithmically controlled LEDs

#32

Post by HeyLaughingBoy » Fri, Jan 25, 2013, 10:18 PM UTC

nathanstitt wrote: post #29

nitrogen wrote: post #28

Earlier quoted context omitted.

When I was in high school (or shortly thereafter) I was working on a circuit that would use 74-series logic to let me clock out 64 LED states 8 bits at a time through my PC's parallel printer port, but got distracted by more pressing projects. There are some serially controlled LED lighting strips, where each LED shifts its state to the next LED when it is given a new state. Thus, to set the state of a strand of 100…

Yes, I'm aware of the strips and have played with the ones from sparkfun. Those are really cool but I want to individually wire and control tiny led's onto a device. Picture a christmas tree that you could do effects on using the lights. Actually what I want to do is embed them into the plaster on a wall during a renovation to make it twinkle and change colors.

It's not at all difficult to build. However, if you really want the LEDs controlled individually, the problem will be the large number of connectors and wiring.

If we assume that, as in your other post, you want to connect 100 RGB LEDs, then you need 100 four-terminal connectors. Assuming you are using 0.1" spacing (I find smaller spacing connectors to be unreliable), each connector will require at least 0.5"x0.75" of PCB space (you need to leave room to be able to plug/unplug the connector). Next each LED will also require a mating connector and 4x whatever length of wire you need and a mounting method.

The first time I had a client who asked me to make up wire harnesses of 60+ wires, 4 feet long, it was a huge surprise just how labor intensive it was to build a dozen of them. And copper is heavy

Re: SF Bay Bridge + 25,000 algorithmically controlled LEDs

#33

Post by nathanstitt » Mon, Feb 04, 2013, 4:13 PM UTC

HeyLaughingBoy wrote: post #32

nathanstitt wrote: post #29

Earlier quoted context omitted.

Yes, I'm aware of the strips and have played with the ones from sparkfun. Those are really cool but I want to individually wire and control tiny led's onto a device. Picture a christmas tree that you could do effects on using the lights. Actually what I want to do is embed them into the plaster on a wall during a renovation to make it twinkle and change colors.

It's not at all difficult to build. However, if you really want the LEDs controlled individually, the problem will be the large number of connectors and wiring. If we assume that, as in your other post, you want to connect 100 RGB LEDs, then you need 100 four-terminal connectors. Assuming you are using 0.1" spacing (I find smaller spacing connectors to be unreliable), each connector will require at least 0.5"x0.75" o…

Yes, I'm not looking forward to the wiring/soldering job that's for sure. An affordable switching driver is what I was missing, but have just found one. Thought I'd better circle back here and drop a link in case anyone else has a simular need: http://www.brilldea.com/product_LEDPainter.html