Alt-BEAM Archive
Message #00263
To: beam beam@corp.sgi.com
From: Richard Piotter richfile@rconnect.com
Date: Sun, 07 Feb 1999 17:18:31 -0600
Subject: [alt-beam] Odd Microcore Anomaly
Everywhere I've gone, I've seen the microcore wires as follows...
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Nv | \
>---||---o---| >o---o---> next Nv
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< |/ |
> v
< Out
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=
I was drawing out my PCBs on the computer to put on my web page (3 diferent
H-Bridges, and 3 types of Nv networks). I looked at actual PCBs I have built and
WORK to this day, and they are wired as follows...
Out (to an H-Bridge, which has a 74HC14 inverter as it's input)
^
Prev | |\
Nv | | \
>---||---o---| >o---> next Nv
| | /
< |/
>
<
_|_
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I've been using an H-Bridge design that uses a pair of inverters, right off the
74HC14 chip, so I decided to keep using it for BEAM. The resulting circuit then
has 2 inverters attached to the same RC circuit. Interestingly, I can grab the
legs, hold them, even turn them opposite of their turning direction, and the
Microcore will not saturate.nk that is due to isolation, but still, two
microcores have been built this way and I didn't even realize it! Both used the
same inverters. My latest work was that branched Bicore. It uses the traditional
output of the inverter going to the H-Bridge. Has anyone ever made this mistake
before and observed it's results? I've drawn the PCBs in the traditional form. I
can and probably will add originals just for the Walkman Jr. section. I have
already made half a dozen new images. I'll have them posted this week, and will
let the list know when they are up. The update will incluse a circuits section
which has PCBs and schematics of 2 types of H-Bridges (3 PCBs are shown). It'll
also have 3, and maybe 4 Nv circuits, if I include this weird one.
Richard Piotter
richfile@rconnect.com
The Richfiles Robotics & TI web page:
http://members.xoom.com/richfiles
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