Really excellent book online from Camenzind

[bcarso]

Thanks to mediatechnology for mentioning Hans Camenzind and provoking the google that led to this. Maybe it's been posted before but I missed it or forgot it. He's happy to have it downloaded, just don't do your own publishing of it. It's also available in hardcopy from Amazon etc.

http://www.designinganalogchips.com/_count/designinganalogchips.pdf

 

[JohnRoberts]

Smart dude, "Mr 555". I recall his company (with Jim Ball? and others) making semi custom ICs "monochips" after he left Signetics. We used them (a 4 monochip solution) for a first generation product at a company I worked at in '70s.

JR

 

[JohnRoberts]

That's it. Interdesgn, I forgot the name (CRS syndrome). Those monochips were crude and limited but pretty damn hip for the early '70s. Sometimes I wish I had some discrete transistors with multiple collectors etc,,,

but again quickly becoming academic or archaic. I'd like to hear about how the IC designers got the new generation opamps so linear.. Probably more than just improved process characteristics. Some times it's hard to follow real IC designs because they make such weird devices with how they assemble the sundry junctions.

JR

 

[JohnRoberts]

the calculus has changed when picking and placing the part cost more than the part.. we are on slippery slope to higher and higher levels of integration.

JR

 

[recnsci]

[quote author="JohnRoberts"] I'd like to hear about how the IC designers got the new generation opamps so linear.. Probably more than just improved process characteristics.
[/quote]

Some time ago I was investigating
a lot of these now flashy opamp datasheets. IIRC ther was a bit of a patern
which intrigued me. Most of devices were folded cascode design with
some serious active loads on cascodes. And output stages are isolated from
VAS by what seems like emiter folowers (check AD797 datasheet, page 11).
What I still dont know is does this output configuration works like
translinear loop (which would mean that neither of output drive transistors
ever goes into full cutoff, nad I dont know would this improve linearity
over plain class B stage).

And yeah, Camenzind book is very nice, plus it's very easy reading. I think
I stomped it in about two days.

cheerz
urosh