[sdiy] A (slightly) better VRef?

[David G Dixon]

> If on the other hand you want an absolute reference voltage, 
> then this is not the circuit to use.  In fact you shouldn't 
> be using Ex.2, either.  These days there is little to no 
> reason to employ something like this, a proper fixed 
> reference IC (or adjustable is you prefer) will give you a 
> much more stable reference.

I concur.  Use a REF02 or one of it's siblings for this application.