[sdiy] ad844 current feedback amplifier??

[lanterma at ece.gatech.edu]

On Dec 13, 2010, at 2:35 PM, Speth, John wrote:

> Historical tidbit: The PAIA modules designed in the 70s used the LM3900 in many designs.  IIRC, the LM3900s were used in the VCA, VCO, VCF, and sequencer.  In the sequencer, I think LM3900s were used as shift registers.  You could tell it was the designers' (John Simonton, perhaps) favored part.  See http://paia.com/manuals/

Interesting!

> While following this thread I was wondering if a "current feedback amplifier" is another name for a "Norton amplifier" which is the LM3900's moniker.  Does anyone know if they're the same?

From 

http://books.google.com/books?id=eknqFp-rY4YC&pg=PA125&lpg=PA125&dq=current-feedback+norton&source=bl&ots=Reu9Y26t59&sig=Gnes0lynxqNuXts3iD9d8uaNklY&hl=en&ei=DngGTZH3HoT58Aby_tzgCg&sa=X&oi=book_result&ct=result&resnum=5&ved=0CDIQ6AEwBA#v=onepage&q=current-feedback%20norton&f=false

"This chapter is devoted to simplified design with current-feedback amplifiers, sometimes called Norton amplifiers, CFAs, or CFBs, depending on which literature you read."

- Aaron