01 August 2011

National App Notes

Last Thursday, I mentioned the National Semiconductor Application Note 294 that Jim wrote. On Friday, a commenter referred to a circuit in NSC App Note 299 (which Jim also wrote).  Jim worked for National in the Linear Integrated Circuits Group from 1979 to 1982. During this period, he wrote many app notes, but getting a complete list of his notes is a bit of a mystery hunt. There are several unfortunate reasons for this difficulty:
  1. National doesn't always print bylines with author's names on their app notes.
  2. National regularly deletes old app notes from their archives.
  3. National sometimes updates the publication date of their app notes upon revision.
However, I spent some time digging, and I think I now have a complete list. To find which application notes he wrote, I had to infer Jim's authorship based on the right time period and other clues. One reliable clue was the inclusion of photographs of Jim's Tektronix 556 oscilloscope with the damaged graticule. In other cases, I made educated guesses based on his use of references, footnotes, or subject matter. A reference to one of Jim's past publications is a good hint, a footnote discussing the Hewlett Packard HP200 oscillator is a dead giveaway!

Based on this research, there are (at least?) twenty-one application notes that he wrote.  They are App Notes 256, 260, 262, 263, 264, 265, 266, 269, 272, 285, 286, 288, 289, 292, 293, 294, 295, 298, 299, 301, and 311. Not bad for three years' work!

You can find most of the app notes on National's master list.  For more details on the frustrations of this mystery hunt, see http://web.mit.edu/klund/www/jw/jw-nsc.html.  (After I finish reading all of the Linear Tech app notes, it will be interesting to go back and reread all of his National app notes.  I should have done that first.)

1 comment:

Robby Beard said...

Application note 272 Op amp booster designs, specifically the "Son of Godzilla" booster is the reason that I even know anything about Jim Williams, and this website. It has taken me almost an entire year to finally find the TY-85 transformer used in that booster, mainly because they're so old that no one sells them anywhere, but now that I have all the parts, I almost have the whole thing built, but I do have quite a few questions about it.