I saw the thread about the led cube and thought about making one myself. The problem is I do not know much about electronics. I've made a circuit but i am not sure of certain things. If you don't mind i would like to get some feedback about the circuit. The circuit will run on 5v and be connected to the parallel port of my pc. The leds forward voltage is 3.5V and current 30mA. Each "A" goes to a line of 5 leds as shown in the upper right corner. "B" controlls the 5 horisontal planes of leds. And "C" controlls the 5 vertical planes of leds. AP, BP and CP goes to a controller board. the APs and BPs are controlled by 74hc138s. The CPs are controlled by a 74hc164. Only one AP,BP,CP can be high at the same time. All transistors are 2n3906. Do the transistors need a resistor at their bases? Does the value matter?
you know what would be a cool application for it...? Use it to demonstrate basic chemistry - unit cells, packing structures, vector direction and plane locations, etc. Some of that stuff is hard to visualize in real life.
Haven't checked in here for a bit, saw this thread and it caught my eye. I've been interested in building one of these ever since I saw James Clar's some time ago, but the cost was a factor. I've recently found several sources of cheap led's. These looked like a good candidate because they are : A) Cheap, only $19.99 + ship for qty 1000 red 5mm B) 120' Wide angle view, figuring most of the points in the cube will be viewed around 90' C) Milky clear, might be a personal preference, but I think that might aid differentiating on/off and better interior view D) Located in CA, so US shipping should be quick and trouble free Many of the clear and super-brite leds have a pretty narrow view angle, it seems to me the view angle might be more important than the concentrated illumination pointing straight up. I've ordered a pack of 1000, we'll see how it goes. My original plan was to use a smaller 8bit AVR because I haven't yet migrated to surface mount packages (prefer dip), but I'm now thinking a project of this complexity might benefit from a single microcontroller that offers more IO. The Atmel 1280/2560 has the same familiar architecture of the smaller AVR's, but offers up to 86 IO pins. That would allow direct control of an 8x8 matrix, similar to what they are doing here with a fpga. Sure would eliminate a lot of driver circuitry. And refreshing a plane at a time should provide better led brightness efficiency. Maybe I can salvage a tqfp socket from some junk and hardwire it?
Some poking around turned up a couple of chips to think about that would require fewer io lines and allow an easier to work with dip ucontroller... the MIC5841 is similar to the 2803 array, but includes a serial->parallel latch. Another candidate would be the MM5450 is a serial->parallel latched led driver capable of driving up to 34 leds at a time. Both are inexpensive and available through Digikey... Thoughts? BTW... not only is it likely easier to assemble using some type of array or driver chips (compared to dozens of discrete transistors with required base resistors), it seems to be cheaper as well. For my 8x8 matrix, 8 x 2803 = $5.52 (.69 ea) vs 64 2n222 or similar npn transistors @ .35 ea = $22.40. I wasn't expecting that, but it works in my favor!
So, this is my current prototype design, requires only 10 I/O bits, multiplexes one plane at a time (up to 64 led's on at once). Not shown are the current limiting resistors between the leds and the 5841 drivers (64 total). Although the MM5450 chips would have cut down the parts count, I don't think the 15ma nax current they provide would be sufficient. Parts: 8 X Pchannel power mosfets (IRF9530?) 8 X MIC5841 drivers 64 X 1/4w resistors (100 ohm?) 512 leds
I thought so too... I think that was Jameco pricing. I don't often purchase transistors, as I'm usually able to scavange them from items in the junk pile...
I have project with led 3d cube 10x10x10. But I'm confuse about wire from microcontroller to led 3d. I use 16F877A, but every port only 8 pin. If I use 74HC138 for decoder that how can I do? Help me! Thank! http://machdienlythu.yforum.biz/forum-f1/topic-t141.htm#360
I try to finish the circuit but I don't know about programing with led cube. If we have 10x10x10 then in 1s, we scan 100 times. so we can how many time for scan this cube? help me! thanks!
I try to finish the circuit but I don't know about programing with led cube. If we have 10x10x10 then in 1s, we scan 100 times. so we can how many time for scan this cube? help me! thanks!
I have finished this hareware 10x10x10. now, I have to finish firmware for my project. anyone has idea!
That's the difficult bit. You may struggle with using such a basic processor since you need 125 bytes to store just one frame (if you intend on storing each frame separately). If you were planning on doing image processing as opposed to storing each frame, you'd want a processor with better mathematical capabilities otherwise you'll have no time to drive the LEDs!
Hi I'm from Bulgaria, and my english is soo bad. sorry about that I was made a 3d cube 8x8x8, for control I use only 8 registers 74hc373 and output bufers ULN 2803 for 64 columns and 2 L293 for 8 stears(rows). The controler is 18f4550. I culd explain in english how is work the program, bud its work The problem I have now is , don't no haw make the picturies, for each frame need 64 bytes of information.
hello every body! I have finished my project welcome to see it http://clip.vn/watch/led-3d-lan-6/WuGL,vn
Sort Led 8x8x8 I have a proplem with sort led by 8x8x8 ! can do it at Led cube ... help me soloved !...
That must be the most miss-spelled thread revival ever. What are you actually trying to get help with?
