[sdiy] Powering ICs from a Voltage Divider

[David G. Dixon]

> >> If your circuits are low enough currents to power from an op-amp why
> >> not just add a TO-92 regulator?
> 
> Because I'm an impatient cheapskate? :) No - I still might. One thing that
> appealed to me about the op-amp idea is that I could use a trimmer to get
> an exact voltage - no having to worry about tolerances.

The perfect solution to this problem is the LM317L 100mA, 3-terminal,
adjustable regulator in the TO-92 package.  See datasheet here:

http://www.fairchildsemi.com/ds/LM%2FLM317L.pdf

It will put out any voltage between 1.2V and 37V with a trimmer, and costs a
whopping 43 cents each at Digikey.