So you think you understand simple circuits.

thatoneguy

Joined Feb 19, 2009
6,359
That paper is similar to the logic gate argument, currently ongoing in off-topic. Though this paper is correct.

What is taught is based around abstractions of Maxwells equations, giving us Kirchhoff's Voltage/Current laws, Thevenin Equivalent, etc. The main boundary for those equations is to assume everything happens simultaneously, circuits are continual, etc. The second boundary is no energy is propagated out of the circuit (RF).

When walking out onto the realm of RF, you leave that sandbox a bit. Voltage at 2 points in a wire may not be the same potential (as is assumed in circuit analysis).

There are a few other issues with high speed logic that make zero sense, unless analyzed "above" a layer of abstraction (logic -> analog -> RF). Results of this are obvious when you look at video cards, and see traces apparently squiggling along, that is a "kludge" to make sure all the bits on a parallel bus "arrive" at the same time for the clock. That speed is something we assume does not exist in sub 100Mhz circuits, but turns critical as clocks crawl higher in the RF range (300-500Mhz+).

IOW, It is a good paper, it's not telling lies, but it also can confuse people new to electronics the same way direction of "electron flow" frustrates them to the point of giving up.

I do hope others, once they know "the basics" with abstractions, see and learn from that paper though. The paper explains in simple terms some behaviors where people tinkering around think they found something for nothing. I would say the tone is a bit hostile, but that doesn't mean the information is pointless/untrue.
 
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