Re: how to control LED array?

John Fields <jfields@xxxxxxxxxxxxxxxxxxxxx> wrote in
news:07bo615abq9oqkfn99no1gap9m1sai0fb7@xxxxxxx:

> On Sun, 24 Apr 2005 22:52:26 GMT, Michael Noone
> <mnoone.uiuc.edu@xxxxxxxxx> wrote:
>
>>Hi - I'm working on a project to make an 8x8 LED array. The idea is
>>that the anodes in each row are tied together, and the cathodes in
>>each column are attached together, giving me 16 pins which I can
>>control 64 LEDs with. But now the only problem is making sure they get
>>the right current/voltage? My plan is to only have one column turned
>>on at any given time, but then any number of the 8 LEDs in that column
>>could be on at that time, so things get a little difficult. I could
>>apply 0 and 5V then just have a current limiting resistor on each LED,
>>but that would be cumbersome and awkward. My end goal is to be able to
>>drive this with 16 pins from a microcontroller. Hopefully I'm being
>>somewhat clear about what I'm asking. Does anybody have any
>>suggestions as to how I could do this? Thanks so much,
>
> ---
> Do you want to control only one LED at a time or any number of LEDs up
> to and including all 64?
>

Hi Mr. Fields - I'd like to control as many at a time as possible. My plan
was to control one column at a time, and cycle through each column about
100 times per second. Does this seem like a good path to take, or is there
a better way to accomplish this? I thought that this method would allow the
board to be fairly simple (anode traces on the top of the board, cathode
traces on the bottom), and would be fairly easy to control (just 16 control
lines). Thanks,

-Michael. J Noone
.

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