Go Down

Topic: 5x5x5 LED cube help (Read 7093 times) previous topic - next topic

CrossRoads

You are misunderstanding - only 5 LEDs at a time will be on. That's why the discussion of cycling thru the 5 groups, and the 5 layers.
5 x 20mA = 100mA max.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

suicidalacorn


You are misunderstanding - only 5 LEDs at a time will be on. That's why the discussion of cycling thru the 5 groups, and the 5 layers.
5 x 20mA = 100mA max.

oh ok. now i understand why you broke it up into sections. that makes sense now. so i wouldnt even need an external power supply for this since it will be using very little power. correct?

CrossRoads

Correct - no external supply needed. Use superbright LEDs tho.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

suicidalacorn

#33
Jan 18, 2013, 03:20 am Last Edit: Jan 18, 2013, 03:23 am by suicidalacorn Reason: 1
so does that mean i can use the pwm ports on the arduino? i do believe, if i remember correctly, the arduino uno has 5 pwm pins.
*edit: i looked it up and it has 6 pwn pins

CrossRoads

Yes.
An Uno has 6 - 3, 5, 6, 9, 10, 11
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

suicidalacorn

awesome! thank you so much for all of your help! i really do appreciate it! ill try to post pictures of the finished cube when i finish it. i do believe i have all the information i need to feel comfortable ordering parts and not worrying about buying the wrong things.

Hippynerd

#36
Jan 18, 2013, 05:27 pm Last Edit: Jan 18, 2013, 05:51 pm by Hippynerd Reason: 1
I really want to build one of these, sadly I have a lot of things going on, so not sure when i will be able to get around to it. The difficulty, as I see it is the isolation of each row. I will be curious how you work that one out.

Thanks again crossroads, I may build one of these, but mostly I really like the idea. Nice work that.

After typing this post, I had a crazy idea. RGB LEDS. It would need a total of 25 control lines. I suppose you could do bi-color LEDs using a total of 20 control lines.
https://sites.google.com/site/rgbledcubes

CrossRoads

Yes, having 5 isolated groups per row would make it a little trickier mechanically vs having the whole layer connected.

RGB, yes add 10 more control lines.

Could use '1284 for that, 32 IO total. Could achieve same update rate, send out 2 bytes of anode info vs just 1.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

Hippynerd

you would be doing 300ma, instead of 100, You might not even have to use different transistors for the sourcing, so it sounds like you could do this without having to change anything else.

It seems to me that you could also do the anodes differently, like with shift registers or LED drivers. I wonder, if you serialized all the data, could you run this off an attiny?

That 32kb data limit may be an issue too, it seems that isnt much space for 4x4x4 RGB cube, and a 5x5x5 is twice the data.

I was thinking about the mechanical aspect, and Im thinking if we turn it on its side, so that the 25 freestanding iines of LEDs mounted to the bottom plane, (similar to the charliecube), it might work. I will have to ponder this a bit more.
https://sites.google.com/site/rgbledcubes

retrolefty

I might add from experience building a 5x5x5 led cube to be sure to use diffused leds as the brighter leds are too directional in their light to give good observation from wider angles of view. Narrow spread leds will have a negative effect on a lot of the visual pattern effects, where diffused leds give better consistent views.

Lefty

CrossRoads

I've read of people lightly sanding them to diffuse them, dipping white paint, putting a white ping pong ball over them ...
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

retrolefty


I've read of people lightly sanding them to diffuse them, dipping white paint, putting a white ping pong ball over them ...


Yea but doing that for 125 leds can get very boring after awhile and it's just makes more sense to buy diffused leds in the first place. They don't carry a cost penalty.

Lefty

suicidalacorn

i bought 10,000mcd LEDs because i figure i can always make them dimmer with code or resistors, but if i get like 1,500mcd LEDs i cannot make them brighter. CrossRoads also recommended high brightness LEDs. unfortunately they did not come diffused, so i plan on putting them in a drill and using that to sand them down. i know it will be a lot of work, but oh well. i wanted the higher brightness LEDs to be safe and not risk having a super dim cube.

edit: this is the link to the LEDs i bought. i bought 2 lots.
http://www.ebay.com/itm/100-x-3mm-round-Blue-LED-superbright-bulb-lamp-light-/230634491097?pt=LH_DefaultDomain_0&hash=item35b2e30cd9

retrolefty


i bought 10,000mcd LEDs because i figure i can always make them dimmer with code or resistors, but if i get like 1,500mcd LEDs i cannot make them brighter. CrossRoads also recommended high brightness LEDs. unfortunately they did not come diffused, so i plan on putting them in a drill and using that to sand them down. i know it will be a lot of work, but oh well. i wanted the higher brightness LEDs to be safe and not risk having a super dim cube.


But then again diffusing the leds will take the same light output of the led and spread it over a wider beam, so I don't think you gained anything by starting out with 'high brightness' in the first place just to then sand them down Vs getting diffused leds in the first place. However the proof is in the tasting of the pudding so maybe when you are done get a single diffused led of the same size and see if you did indeed gain any overall brightness.

Lefty

CrossRoads

Sanding them to diffuse the output I am sure will be a lot less work than the actual assembly and all the lead bending/alignment prior to soldering that is needed for cube stability and overall squareness.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

Go Up