[sdiy] IN your mind, what is ....

[Ian Fritz]

At 04:48 AM 1/30/2004, jhaible at debitel.net wrote:

>Sure. Maybe it even was the other way round, and the LM3900
>first coined that word, Norton opamp?

Before today, I can't remember ever seeing the term "Norton opamp".  In 
AN72 it is refered to as a " 'Norton' amplifier".


>Yes, that's technical progress ...
>Today's state of art is tomorrow's junk - or vintage device, depending
>on your application. For many audio applications, you don't need
>an "operational" amp at all - you just need an amp. Discrete, when
>I have the choice. And with a single transistor input stage, because
>the second half of a differential pair will add 3dB of noise. (;->)
>(But then again, try building a GIC or FDNR filter from a LM3900 or a
>Philbrick opamp ...)
>
>BTW, when Harry speaks of Bob Pease dissing that LM3900 (Hi Harry!)
>this is from _today's_ point of view. Back then, he wrote the
>foreword to that Fredriksen Book where the 3900 is presented as an
>important part of National's opamp history. And he gave me that book
>with the comment that it's still valuable reading today. (;->)

Say what you will about the 3900, it is still in production.  Somebody must 
be using it for something (or is it just for replacement/repair?).

   Ian