<html>
<head>
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
</head>
<body bgcolor="#FFFFFF" text="#000000">
<div class="moz-cite-prefix">Hey Hilaire, <br>
Thanks for the reply. <br>
<br>
The TD62783 is a Darlington array, I added it to this design so it
should be fine now. All the current for the LEDs will be handled
fine (and within specs) of the TD62783 and the 3 TLC5916 chips. I
was actually more interested in comments on the routing of the
board, and best way to source parts. <br>
<br>
Is your place in West Oakland BART accessible? I live in Concord,
but usually take BART to work in SF. <br>
<br>
Thanks,<br>
Daniel.<br>
<br>
On 1/23/14 11:42 AM, Hilaire Nollette wrote:<br>
</div>
<blockquote
cite="mid:CAPGO28t30mxB=oY_tvRWKD3xgXJhijr5FC9MPkS7BbDiZGjpXQ@mail.gmail.com"
type="cite">
<div dir="ltr">
<div>
<div>
<div>Daniel,<br>
</div>
Looks like you are trying to drive the whole matrix with one
chip, in this arrangement you'll need Darlington arrays,
that chip won't drive a matrix directly, I am willing to
either face2face at Noisebridge, or you can come to me in
West Oakland, I have an electronics lab here. the way you
have it setup you are driving too many led's from one pin,
120MA maximum per chip. What you'll need is something like a
2N3096 on each leg of the chip driving the array. I can show
you samples of all of this, as well as proper current
limiting.<br>
<br>
</div>
Let me know,<br>
</div>
Hilaire <br>
</div>
<div class="gmail_extra"><br>
<br>
<div class="gmail_quote">On Thu, Jan 23, 2014 at 11:05 AM,
Daniel Pitts <span dir="ltr"><<a moz-do-not-send="true"
href="mailto:Daniel@coloraura.com" target="_blank">Daniel@coloraura.com</a>></span>
wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">I have a
design for a project, and I was hoping to get some
face-to-face feedback on the design. I was thinking
Noisebridge might be a good place to do that.<br>
<br>
It seems that Circuit Hacking Monday's would be a good time
to do that, but I would like to see if someone with
experience/expertise would be willing to meet up with me at
that time specifically to look over it.<br>
<br>
Board (PDF): <a moz-do-not-send="true"
href="http://virtualinfinity.net/electronics/LED%20Display%202%20-%20board.pdf"
target="_blank">http://virtualinfinity.net/electronics/LED%20Display%202%20-%20board.pdf</a><br>
Schematic (PDF): <a moz-do-not-send="true"
href="http://virtualinfinity.net/electronics/LED%20Display%202%20-%20schematic.pdf"
target="_blank">http://virtualinfinity.net/electronics/LED%20Display%202%20-%20schematic.pdf</a><br>
Board (EAGLE): <a moz-do-not-send="true"
href="http://virtualinfinity.net/electronics/LED%20Display%202.brd"
target="_blank">http://virtualinfinity.net/electronics/LED%20Display%202.brd</a><br>
Schematic (EAGLE): <a moz-do-not-send="true"
href="http://virtualinfinity.net/electronics/LED%20Display%202.sch"
target="_blank">http://virtualinfinity.net/electronics/LED%20Display%202.sch</a><br>
<br>
The goal of the project is to build a programmable 8x8,
12bit color LED display, and to do it "cheaply", while still
maintaining some level of quality. I had a prototype
working, though it didn't support the full amount of current
required. It worked when powered from a battery, but burned
out a chip when I used a real power supply (the 74HCT238).
I added a high-side driver to fix that issue.<br>
<br>
Anyway, if someone would be interested in talking with me
about this, then I'll try to show up on a Monday night.<br>
<br>
Thanks,<br>
Daniel.<br>
_______________________________________________<br>
Noisebridge-discuss mailing list<br>
<a moz-do-not-send="true"
href="mailto:Noisebridge-discuss@lists.noisebridge.net"
target="_blank">Noisebridge-discuss@lists.noisebridge.net</a><br>
<a moz-do-not-send="true"
href="https://www.noisebridge.net/mailman/listinfo/noisebridge-discuss"
target="_blank">https://www.noisebridge.net/mailman/listinfo/noisebridge-discuss</a><br>
</blockquote>
</div>
<br>
</div>
</blockquote>
<br>
</body>
</html>