Showing posts with label EE. Show all posts
Showing posts with label EE. Show all posts

Wednesday, October 1, 2014

Relevance of electrical impedance?

How is electrical impedance relevant in real world applications...?

Rawk music! Seriously, though - there's an analysis of the commonality of high and low impedance signals in audio systems, including band systems -- along with a broad review of electrical systems theory -- from Whirlwind Music Distributors, Inc. 

Of course, remembering that a digital circuit's data sheet may denote an "Unkonwn" quality for a digital logical element, in a situation of "high impedance", certainly electromagnetic impedance would be a relevant quality in digital circuits, too? (Candidly, it might be difficult to find any sort of research about the same, but I'll check  Google Scholar , too.)

So, after checking the research more, it looks like there are applications for analysis of impedance, in industrial power systems, viz a viz:
So, I suppose that's towards applications in industrial electronics. Perhaps it's simply a quixotic idea, to wonder if there's a relevance of impedance in digital microcircuits?

Certainly towards an application in digital measurement technology, thence perhaps applicable towards semiconductor design: Smyrl, William H.  Digital Impedance for Faradaic Analysis published by the Journal of the Electrochemical Society, no doubt a peer-reviewed journal. Perhaps the article is more in reference to Dielectric Spectroscopy , however --something certainly about microscopic qualities within electrical circuits -- perhaps less immediately relevant, if with regards to immediate calculation of electrical impedance within an analog circuit.

Other than the textbook from GE Digital Energy, those formal articles are all limited-access, however -- requiring a subscription of some kind, if not a per-article fee -- to simply read about the existing academic research, at least at those web resource pages. Perhaps a pre-print PDF edition might be available of any of those articles, however, via a simple, quoted "Google Search" -- if not a similar search, via Google Scholar -- of any of those article's "Title" texts? "YMMV" I'm sure.

Reading the Wikipedia article about Dielectric Spectroscopy, however, I think that that article seems to go well into a depth of explanation, perhaps serving to explain what's some of the science underlying the impedance calculations, in these matters of circuit analysis

Monday, June 2, 2014

Papilio and Xilinix FPGAs

I've recently begun to study FPGA programming, albeit through kind of an impractical program at DVUO. In a small, practical regards, the course focuses on Altera FPGAs and Altera's free and unsupported (?) Quartus II Web Edition as -- basically -- lab kit items for the course at DVUO. I constantly have to "Do some additional reading," to get anything out of the DVUO courses. Personally, I'm not studying up for "Signing off at the Blarney Stone."

In that additional reading, I have learned:

In addition to the Altera FPGA line, Xilinix also manufactures FPGAs, such as the Xilinix Spartan 3 and Spartan 6 FPGAs.

Spartan FPGAs are available in the "DIY" electronics market, on the Papilio -- alternately, ZPUino -- FPGA boards, such as the "Papilio pro".  The  software tooling for Papilio is more bear-bones than Quartus -- the former, extending on the Arduino programming toolkit.  The Papilio toolkit uses a bitfile format for direct programming of the FPGA. Papilio boards can be programmed with Papilio's ZAP IDE and the Xilinix ISE WebPack.

A Papilio board can be extended, in its hardware, with a "Wing" or "Megawing", such that essentially "plugs into" I/O headers on the Papilio circuit board.

Papilio is an open platform, and thoroughly supported for programming on Linux and on Microsoft Windows.

Ostensibly, Papilio, too, can be used to simulate a full multiplexer or demultiplexer, or alternately a single 74138 or 74148 circuit's logic profile, in today's world o' technology. We've studied the latter at DVUO -- something of some allegedly "common" integrated circuits, really difficult for this student, me, to find any applications for, or any sense of relevance about, in the regards to the industry, today. Perhaps it makes more sense in a broader circuit with clock synch, and as an artifact of an at least historic technical interest. So maybe I, too, can believe in magic beanstalks, after all -- if only those beans were just as good in an "unsmart" crock pot.

Works Consulted:
[1] http://www.xilinx.com/products/silicon-devices/fpga/spartan-6/
[2] http://papilio.cc/index.php?n=Papilio.ZPUinoIntroduction
[3] http://papilio.cc/index.php?n=Papilio.ArduinoCore
[4] https://github.com/GadgetFactory/Papilio-Loader/blob/master/xc3sprog/trunk/bitfile.h
[5] http://papilio.cc/index.php?n=Papilio.Hardware
[6] http://gadgetfactory.net/learn/2013/10/29/papilio-schematic-library-getting-started/
[7] http://gadgetfactory.net/learn/2013/10/23/install-xilinxs-free-ise-webpack/
[8] http://www.xilinx.com/products/design-tools/ise-design-suite/index.htm
[9] http://www.xilinx.com/products/design-tools/ise-design-suite/ise-webpack.htm