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On the wikipedia page for BJT biasing, there are about 4 different biasing methods discussed. I can analyze and understand each one of them, however I want to know how and in what order people came up with them - what problems they had and how they tried to solve them. From what I know, most of the time you would use a voltage divider with emitter degeneration, however that doesn't look like it was the first thing people thought of when they wanted to do biasing. For example, I would assume that someone first just tried a fixed bias, but then realized that it doesn't account for beta variations and is unstable, etc.

I'm happy with either a comprehensive answer or some kind of reference to a book, article, paper or anything really. I'm asking this because I want to go through the same process myself in order to better understand things.

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The world of vacuum tubes also has a variety of biasing methods, including the "grid leak" method where SOME grid current is assumed.

Chances are there is nothing new under the sun, for bipolar biasing.

Examine Tube Manuals (RCA, Sylvania) and the TV_repair packets (SAMS) for those 300 watt TVs.

Bipolars are just like vacuum tubes:

  • amplification comes from Transconductance * Load_Impedance

  • Miller Effect eats up your high frequency energy

  • The Early Effect in bipolars is much worse in triodes, and much reduced in pentodes, but that slope of I_V output characteristics is a part of all design in_the_trenches.

  • the distortion is strongly affected by biasing

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  • \$\begingroup\$ 1950s texts would be useful for a historical study : Germanium transistors needed more careful biasing to avoid self-destruction on "thermal runaway". \$\endgroup\$ – Brian Drummond May 13 at 12:23

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