How to Multiplex/ Part II

In this video, we continue to figure out how to control 64 LEDs with 12 pins. These techniques can apply to a larger "grid" of LEDs.

http://www.kevindarrah.com/

Category:

Science & Technology

Tags:

• arduino
• LED
• cube
• microcontroller
• pic
• multiplex

[mallemang]

Great job on the video! I'm going to try a variation....for the Anode transistors...don't need base resistors (emitter follows the base just 0.6V lower). And for the Cathode transistors, I'm gonna try PNP also in emitter follower configuration...the big difference is that now you pull the base LOW in order to turn on the Cathode transistor...but that's no big deal with the Arduino right?......so now the only resistors I need are the 4 current limiting resistors...Mark

[kdarrah1234]

@mallemang interesting! My transistor skills are a little weak, there is definitely room for improvement with my method, good luck!

[vicky27287]

i have tried a 5*5*5 led cube and i'm using 8051 micro controller

hmmmm i don't know how to multiplex it:(

could you help me out finding any circuit for tat:(

that to i got to submit it in my college well before 24th:)

[kdarrah1234]

@vicky27287 ouch, the 8051? never played around with that one, should be the same principle as what I'm showing. You may want to consider shift registers, think I made a vid on that

[lilcreazz420]

ok i have to ask what would be the best transister for my 8x8x8 cube

[kdarrah1234]

@lilcreazz420 i would experiment around with a few, but I used standard 2N3904s, just because I had a bazillion of them already

[lilcreazz420]

ok just to tell you all i have multiplex my 16x16x16 cube down to just a 12 pin setup so that the arduino its self can run my cube thanks kdarrah1234 with your help of multiplexing it give me a way of doing it

[lilcreazz420]

OK think about this can i run the arduino outputs to a decoder ic to get more outputs from the arduino by having the arduino send its code to the decoders and have them run the cube

[kdarrah1234]

@kcinkcinkcinnick yep, I'm using the same 5V used to power the arduino, transistors can kind of work like switches. I think I made a vid on that a a while back

[kcinkcinkcinnick]

you have another 5v power source?

so you deactivate a transister just buy putting off a pin from the arduino to the base of the transistor? :p