# LED Cube Using 4020 Ic and 555 IC

33,060

40

16

This circuit drives a 3x3x3 cube consisting of 27 white LEDs. The 4020 IC is a 14 stage binary counter and we have used 9 outputs. Each output drives 3 white LEDs in series and we have omitted a dropper resistor as the chip can only deliver a maximum of 15mA per output. The 4020 produces 512 different patterns before the sequence repeats and you have to build the project to see the effects it produces on the 3D cube.

in 4020 IC the reset pin should not be left free it must be connected to the ground with 100 nf capacitor.If it is not connected the IC will reset again  and  again there will be no output in the output pins.

The speed of the LEDs is controlled by a 10k variable resistance connected to the 555 IC
And the capacitor connected to the 555 IC is 22 uf .

### Teacher Notes

Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.

## Recommendations

• ### Internet of Things Class

22,786 Enrolled

## 16 Discussions

It is being used as a variable resistor so only sweep arm and one fixed terminal are used

This is a blant copy from this website.

Even the text is just copied.

At this stage I assume it to be a fraudulent copy with no credit given to the original author as I don't think Colin Mitchell would use Ahimadu as a username...

hello I have a problem, I rode the original circuit but do not know what goes into the cube are to be switched on and off like a flip flop

someone help me?

thank you

2 replies

Hey can u say that in diagram the desired pin shown should correctly to that ic pin only or I can connect all anodes on different pin shown in diagram please reply quick waiting.....

Ok, so I have almost "made it". The bottom layer is giving me grief. When I ground it, the other two layers go out. When I send the top and middle layers to ground without the bottom layer they work fine. Consequently, grounding the top two layers leaves the bottom layer actually faintly glowing with the patter of the others.???? I have checked for shorts and double checked connections???? Can't seem to find the cause.

I also found that a 22uf Capacitor in conjunction with a 200 Ohm resistor produces a nice fast speed. This is with a 9v battery. A 1K potentiometer might be a great choice for adjustable speed. I spent a little time designing a Fritzing PCB for anyone interested in trying it out. Here is the OSH Park link: http://oshpark.com/shared_projects/jP3Ri1Oo

Attached is the Fritzing image.

Help if you can???

Hope the PCB makes this fun project just a little easier for someone!

I mean that all cathode connected by single jumper and it should connect to negative terminal.

thanks for the instructions.but I made some changes.i used 82 ohm resistor instead of 10k variable resistor and 100uf capacitor instead of 33 uf. akso avoided 100nf capacitor connection. also I used only 9V. it worked greatly.

Does each strip/line has 3 LEDs in series and such 9 strips in parallel ?
Does Red line indicate actual connection or just for visualization ?

Can you also post a better picture of the LED cube

Thanks
Amit