From: Neil <picdude3@narwani.org>
To: "piclist@mit.edu" <piclist@mit.edu>
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Date: Thu, 30 Apr 2020 14:57:38 -0700
Subject: Re: [EE] LED Matrix CC/CA
Thread-Topic: [EE] LED Matrix CC/CA
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Yes, if all the anodes are wired together to the COM pin then it's=20
common-anode.
And vice versa.
Often, I've seen 2 common pins, which is the same common-anode broken=20
out to 2 pins that are internally connected together.

Yes you can use CA or CC, but you're circuit will change, of course.

I generally lean towards CC, because switching on the whole digit (when=20
multiplexing) is easier to have a transistor/FET switch low-side, rather=20
than high-side.

Cheers,
-Neil.


On 4/30/2020 4:20 PM, Josh Koffman wrote:
> Hi all,
>
> I need a quick double check.
>
> I'm looking at using a small 8x8 LED matrix in a project. It's been
> awhile since I've dealt with them. If I recall correctly, in an 8x8
> LED matrix what makes it common cathode or common anode is really just
> how it's wired, correct? Since I'm making my own board, I could get
> either and have it work as long as I adjusted the wiring for the
> correct pinout?
>
> I haven't done a ton of sourcing yet, but a preliminary investigate
> showed CA as a bit cheaper, though the driver I want to use prefers
> CC.
>
> Thank you!
>
> Josh

--=20
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