There is a close 2nd: 70 pV/rtHz test ampliifer in AOE V3 [1], chapter 8.5
No transformers, Zetex-based.
What's the input current noise on that one?
The upstream IC (LT1028) has min GBW=50MHz and is operated at a gain of 39, so its bandwidth is about 1.3 MHz. The AD844 is operated at a gain of 14 and at that gain, has BW of about 33 MHz (ADI datasheet Fig 24). It seems to me the AD844 was used because its bandwidth is 25X higher than the first stage, thus it "stays out of the way" and allows the other, slower, circuits to determine full loop bandwidth. Which appears to be, extrapolating Figure 4, about -3dB @ 400 kHz (-1dB @ 100 kHz).
Hmmm. Makes sense, but still the AD844 is kind of an outlier here. Surely there must be some 'real' opamps that could foot the bill.
Ohh well, designers have their quirks I guess. Present company included ;-)
I hang out at eevblog too. It's interesting to see the difference in goals pertaining to low noise designs.
DIY low frequency noise meter and some measurement result of voltage references - Page 1
DIY low frequency noise meter and some measurement result of voltage references - Page 1
There is a close 2nd: 70 pV/rtHz test ampliifer in AOE V3 [1], chapter 8.5
Fig. 8.37 ?
Patrick
No, 8.42
These small excerpts must be enough.
I don't want that Winfield kills me next time I meet him on s.e.d.
The book is nearly 1200 pages of really good information.
Worth every cent.
Gerhard
These small excerpts must be enough.
I don't want that Winfield kills me next time I meet him on s.e.d.
The book is nearly 1200 pages of really good information.
Worth every cent.
Gerhard
Attachments
I hang out at eevblog too. It's interesting to see the difference in goals pertaining to low noise designs.
DIY low frequency noise meter and some measurement result of voltage references - Page 1
Ahhhhhhhh, yes, design for intended application, useful feedback given on implementation, concise language.
Refreshing isn't it!
Hi gerhard,
Thanks. At least you're referring to a book I already own for once! I agree that it is packed full of information.
-Chris
Thanks. At least you're referring to a book I already own for once! I agree that it is packed full of information.
-Chris
Too late to close the barn door. Link removed by moderationThese small excerpts must be enough.
I don't want that Winfield kills me next time I meet him on s.e.d.
The book is nearly 1200 pages of really good information.
Worth every cent.
Gerhard
That's the 2nd edition only. The 3rd is also on the net.
And there are Chinese paper copies.
The original is cheap enough.
Your post will probably be removed when the first mod sees it.
And there are Chinese paper copies.
The original is cheap enough.
Your post will probably be removed when the first mod sees it.
My link is to a university, not your typical pirate download site. No reason to pull it off lest you want to close libraries too.Your post will probably be removed when the first mod sees it.
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university - not your typical pirate download site
Now there's a laugh, I'm more concerned that a member here would post it.
The second edition is 28 years old! Sheesh! Report me to the mods then! Report the university too while you are at it.Now there's a laugh, I'm more concerned that a member here would post it.
Speaking from my personal opinion, I can't read and retain stuff off a computer. Anyone who would download from the link should probably just go buy a paper copy. They aren't expensive (mine was $25 at a Hamfest). I much prefer reading from something that doesn't need batteries or can be erased easily. To each his own.
There really isn't anything like the feel of a book and sitting under the sun reading, or sitting in a comfortable chair, sipping on whatever you like while reading. I usually have an hour or so to kill waiting for doctors, so there is ample time to enjoy a good read.
I am hoping people might look at the material long enough to discover it is well worth buying. So don't take our word for it, go look and decide for yourself.
-Chris
There really isn't anything like the feel of a book and sitting under the sun reading, or sitting in a comfortable chair, sipping on whatever you like while reading. I usually have an hour or so to kill waiting for doctors, so there is ample time to enjoy a good read.
I am hoping people might look at the material long enough to discover it is well worth buying. So don't take our word for it, go look and decide for yourself.
-Chris
People who is on the road a lot cannot take everything with him.
He will have to either have a soft copy on the laptop, or on the cloud.
Patrick
He will have to either have a soft copy on the laptop, or on the cloud.
Patrick
Robert, I think you're good, Scott's point seems aimed elsewhere.
I'm due to update to the third edition. I partially blame aoe 2nd edition for going EE in undergrad.
Chris, I'd be lost if I had to read everything on paper, but our jobs are different for sure. 🙂
I'm due to update to the third edition. I partially blame aoe 2nd edition for going EE in undergrad.
Chris, I'd be lost if I had to read everything on paper, but our jobs are different for sure. 🙂
Robert, I think you're good, Scott's point seems aimed elsewhere.
No, if mob rule says copyright period should be whatever they want they should live by it and they don't have any reason to complain about any cloning, reverse engineering, or whatever.
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