amplifier stability and compensation

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