[sdiy] LM3900 slamming

[Paul Schreiber]

The LM3900 was the first 'automotive' temp range (-40C to +85C) quad op amp that
was less than 50 cents in 100K quantities. During their heyday (around 1978),
Motorola was quoting Tandy their version (MC2904 I think it was) for 9 *cents*
in 1 million pieces. JRC then counter-attacked, quoting the NJR4558 dual
"cheesy" audio-quality amp for 11 *cents* at 100K and 9 *cents* at 1 million.
Used about 1.8 million 4558s in the TRS-80 300 baud modems and another 600K in
the Model 100 laptop.

Even today, the 4558 is the wold's cheapest minimal-quality op amp. It's
slightly cheaper than second places' MN5218P from Panasonic.

Paul S.