Arduino Microcontroller

[las3r]

hi guys im wanting to build a led sign from 3mm leds and i came across a controller that might be what im looking for....
Arduino Microcontroller

my question is can i run alot of leds from this controller ??

and

is it hard to hook up and run leds from it ??


im not sure how many leds im going to use but i no its more than 50-100

only why i would like touse this controller is because i want my sign to do some cool color effects ect.......

 

[paulr]

There are bunch of different Arduino models (www.arduino.cc). I don't think any have 100's of output pins. You will probably want to use some kind of strobe/multiplex scheme. Do you know anything about digital electronics? About programming? Arduino is a good way to get started but you should first get a reasonably clear idea of what they can do.

 

[PMM]

you only have on the common ones 8 outputs and you'll only be ample to use a single low powed LED,

If the intention is just using the controller to colour switch a pre-built static image there is prob better solutions out there.

But if you did go the Arduino route you would use the output to drive a 2nd circuit to power the LEDS anyway to meet the power requirements.

though using a differing approach some smart colour changing SPI leds coupled with this method of implimenting a sign could be interesting

http://hackedgadgets.com/2008/11/05/arduino-rotating-led-display/

You'll need to be quite handy on the programming side though.

 

[ednspace]

You will not be able to control that many LEDs with the Arduino directly, however there is a technique called multiplexing. Good thing is, there are chips out there that can handle all of this for you. One that I have played with for projects in the past is the MAX7219 The chip is a 7 segment display driver, but it can be configured to drive up to 64 individual LEDs. Also, these chips can be chained together on a communication bus, and in that way drive even more.

Keep in mind there are lots of options when you start looking at port expanders or multiplexers to drive LEDs, seems like almost every company has a solution. The MAX7219 is nice, because you can still get through hole parts, so you can use a bread board to prototype, also there is a driver and examples specifically for the arduino. Check out this page for more info

You might want to get an Arduino starter pack from, adafruit or sparkfun. Then get just a single LED blinking. You will have to invest some time in learning how all the pieces fit together. The Arduino is a great starter development system, as everything is open source, hardware, software etc... Also in the end you have a bog standard ATmega chip, so if you want to make your own boards, you can. Once you get control of that many leds, it can be pretty fun, and the microcontroller opens up lots of doors for other projecets, sensors etc...

 

[las3r]

iv got few inputs from few people and they said to use 555 timer circuits to make different designs using the LED's

but if i do go with the 555 timer circuit what would u think is the best circuit to go with to get a good flashing/fading/ECT.........design ?? any suggestions would be good on what u guys think would be a cool design

 

[SemiMan]

Lasr unless you have some electronics/programming experience this is not that trivial a thing to do.

Generally one uses a microcontroller with dedicated LED drivers for signs like the ST STPIC16D595 or that general range of power logic parts for LED drive in signs. Toshiba, Austria Micro, I think Allegro, etc. have parts too.

If you want to update fast, the micro needs some speed on the serial ports.

Semiman

 

[PhotonWrangler]

Might want to consider the Maxim 6974 or 6975. These are driver chips that are designed for LED signs, and they have a serial interface so that takes care of your output pin limitations.