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It seems like apprenticeship is really the only way to learn this. They don't even teach this stuff in undergrad EE programs.


I find that hard to believe because I can't imagine teaching EE beyond the first year without running face first into impedance. I mean, any time you touch on RF (which is the really interesting part of analog anyway) you have to somehow talk about the difference between DC and AC, unless you talk about it in an exclusively academic way as if it's some EE relic that you'll never use. It might come down to the fact that everyone is taught Ohm's Law first, which for me seems a terrible way to teach EE because it forces an immutable, instantaneous relationship for your circuit (aka spooky action at a distance) whereas impedance has a meaning grounded in how the electrons interact with matter. I threw away everything I learned in EE/ohm's law when my mentor taught me impedance because the mathematics, units, and physical intuition finally fell into place.

The benefit of an apprenticeship is that you are usually taught in a project setting with tools that have this knowledge largely built in. All you have to know is the theoretical implications of each of your use cases (and there aren't many in say, consumer smartphone design, except for the antenna) and what the jargon is for your software. Altium has "matched lengths," "interactive differential pair routing," "impedance matching," etc. which you can use with specific engineering calculators ( http://www.mantaro.com/resources/impedance_calculator.htm is my favorite) and the software will do the rest. Literally, point, click, and drag.


I should probably clarify. What I meant to say is that they don't really teach high-frequency analog design in school. We covered the theoretical aspects, like impedance matching and reflection, but there's a long way between knowing those things and being able to reason with them when designing a chip.


Well if you understood the fundamentals it's actually not that far to being able to design a board. Designing a chip is a whole other matter but can also be quite easy if you are comfortable with FPGAs and using IP cores. I'd say there's about a 0% chance of you having your own fab so the ASIC firm you hire will usually help you synthesize the high level language design to silicon (for a price).

Once you're comfortable with your routing tool, check out the following links. This is the material I use as a refresher when jumping back into high speed digital design:

http://www.ti.com/lit/an/scaa082/scaa082.pdf <-- Check out page 7, has a great diagram for what happens with reflections

http://www.freescale.com/files/32bit/doc/app_note/AN2536.pdf

http://www.altera.com/literature/hb/stx2/stx2_sii52012.pdf


I should mention that I'm a computer engineering major and not a EE major, so I haven't taken some of the more advanced physics classes like solid state physics or electromagnetics. Are there any resources you would recommend for getting more of the theoretical background on those topics?


I've tried to learn the physics behind EE but my brain has been shot too many times by primary through secondary education. As a CS major you can dive in depth into the PCI/DDR standards and they will teach you alot about the signals. Combine it with a application note on DDR routing and you'll get the big picture.




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