[sdiy] Any LM331 experts around?

[Neil Johnson]

Ian,

> Mystery revealed.

And described in:

http://www.stanford.edu/class/ee122/Parts_Info/datasheets/LM331-AN-C.pdf

on page 4.  Courtesy of Mr. Pease, of course.

In your example the transistor is providing the bias, in Bob's example it is two diodes.  But its the same trick.

Neil

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http://www.njohnson.co.uk

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