Aren't they running out of one of your old fabs? Good parts that are well engineered for the applications they're targeting.
Ha ha... but if it sounds the same ad the LM<whatever> part (for all intents and purposes) are they both oscillating?
Having never had one oscillate, what amplitude is the typical oscillation?
Or is it more like a burst parasitic?
(wow, almost real technical content is suddenly breaking out! WARNING WILL ROBINSON!!)
You may want to check the history of the "Superregulator". 😉
Picture here at paragraph H:
https://oriongateway.org/hubble-super-regulator/
😀
Or they respectively got jobs elsewhere and any motivation to further document their efforts was diminished. Although if it make it to preprint, that's a head scratcher, as I haven't seen anything abandoned by the time it hits preprint (or was it a conference abstract?). Academic publications are weird.
Bear (and with absolutely zero insincerity), yes, let's get into technical content. One expects oscillation frequency to be close to the unity gain bandwidth of the opamp. (To a first approximation)
What is Wrong with Op amps?
Mr Hansen stated the simple answer on diyaudio.com many years ago.
The thread is most interesting I've seen and still reading it.
Link:
http://www.diyaudio.com/forums/soli...uilt-non-feedback-amplifier-8.html#post331141
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Mr Hansen stated the simple answer on diyaudio.com many years ago.
The thread is most interesting I've seen and still reading it.
Link:
http://www.diyaudio.com/forums/soli...uilt-non-feedback-amplifier-8.html#post331141
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Attachments
This again proves that any complex question has a simple, wrong answer.
I thought this was debunked long ago.
I mean, if you look around and see a world that functions because it is full of feedback systems. Billions of people riding bikes without falling over. 1000's of planes relying on feedback not to fall from the sky. Equally 1000's of nuclear power plants relying on feedback not to explode. Even your shower relying on feedback to maintain the set temperature.
Now you stand up and say - feedback can't work. That is an extreme case of stupidity!
Jan
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No feedback is perfect. That is impossible. Charles and I, today, and Richard Heyser over 40 years ago, found that negative feedback in electronic circuits changes the sound quality of the amplifier, often for the worse. That has been our experience up to now. That doesn't mean that we don't use feedback when it is necessary to get better measurements, etc.
You misunderstood Dick Heyser big time. He was smart enough, after figuring out what feedback can and cannot do, to continue to use it in a very good way armed with the outcome of his research.
You guys never got further than his 1st paragraph.
Jan
You guys never got further than his 1st paragraph.
Jan
No a foundry. I didn't know they made a broken out version of the pre-amp I'll have to try out a sample. I met Les Tyler, Dave Blackmer, and Bob Adams through DBX in 1977. They were already thinking of integrating their modules.
Yes the feedback goes round and round.
Barrie Gilbert and Charles copied me on a huge multi-page email discussion over the use of the AD844 open-loop. Some here would be spilling their coffee over their keyboards if I posted it, but I tossed it (it was private anyway).
Charles essentially trying to convince Barrie that feedback can't work. Mr. Hansen makes lots of good products why he holds some of his views with such extreme exaggerations I don't know.
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In such cases I envisage two friends walking along the beach and one saying: 'Did you know that water doesn't exist?'
'But, but...'.
'No really, I have it on good authority'.
Jan
'But, but...'.
'No really, I have it on good authority'.
Jan
Someone, I think it was a piece in Linear Audio, put forth the proposition that extremely high levels of feedback (obtained by what means I don't recall, but likely multiple loops) was "better" than "regular" feedback. Iirc, they also said that there was some threshold or another above which things got much better and below which and over a wide range things were not so good.
I may be wrong but I think they also compared the low or zero feedback case to the ultra high feedback case.
Did I imagine this?
Was it Stan Richter, or??
_-_-
(of course feedback "works" as in it serves a function - the question of if the results of said function are beneficial in all cases, and if they cause any deficits or not, aka higher order effects remains. . Clearly for the most observable and often the fundamental aims it's incredibly beneficial... nobody debates this.)
I may be wrong but I think they also compared the low or zero feedback case to the ultra high feedback case.
Did I imagine this?
Was it Stan Richter, or??
_-_-
(of course feedback "works" as in it serves a function - the question of if the results of said function are beneficial in all cases, and if they cause any deficits or not, aka higher order effects remains. . Clearly for the most observable and often the fundamental aims it's incredibly beneficial... nobody debates this.)
Ah, feedback again.... wasn't there a monster thread started by Jan about? If I remember correctly, the contention wasn't whether feedback works or not. It was about whether it works like Jan imagined it would.
- but feedback works, look at this model and the math, it's flawless!
- sure but that model is for infinite bw linear amps with no memory
- but surely it's close enough!
- no it ain't, and btw if you had a device like that you wouldn't need to apply feedback to it
- but feedback works, look at this model and the math, it's flawless!
- sure but that model is for infinite bw linear amps with no memory
- but surely it's close enough!
- no it ain't, and btw if you had a device like that you wouldn't need to apply feedback to it
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