(1) Have your students had passive circuit theory including Laplace analysis, and understand "phase"? You did say "third year"?
(2) Get a copy of Middlebrook's paper that discusses measuring phase margin. (Referenced on my website.)
(3) Drop the "dr" from your E-mail address. I'm very leery of people who are "title-pompous". I knew a fellow from not-a-few years back, a co-instructor of mine, who insisted on being addressed as "mister"... his son is now on death row.
...Jim Thompson
The e-mail is a joke, i'm only 20, so i hardly have a doctorate. I couldn't just use dr_quinn for obvious reasons. Thanks for the continuing input lads, keep it comin...
The best method IME of instruction of pretty much anything is to cover the theory in a practical manner without reams of needless equation that send the students to sleep followed by *practical* demonstrations of how it works.
A good example of the interesting requirements of amplifer stability and compensation can be found in just about any competent discrete audio hi-fi amplifer btw. It's remarkably easy to make a great oscillator.
As for demonstrating the importance of phase margin - why not devise a simple unity gain op-amp circuit that's stable - but with an additional passive phase lag stage from the output, of lowish impedance, that the feedback can be switched to which should then oscillate - then show how adjusting the gain should be able to recover stability. You should also be able to calculate the frequency at which it'll oscillate.
Graham
On Sat, 07 May 2005 14:23:29 -0700, Jim Thompson "" wrote: ^^^^^^^^^^^^
Heh. :-)
Hey, Dr. Quinn was one hot babe! (leer, snort)
Thanks lads, project is done and dusted, thank god, anywho, your time and info is much appreciated
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