[volt-nuts] Homebrew LTZ1000 reference?

[Mike S]

At 10:47 AM 11/19/2009, gsteinba52 at aol.com wrote...
>          Linear Technology has an application note on this very 
> subject:
>
>cds.linear.com/docs/Application%20Note/an86f.pdf
>
>Devour the whole app note

Schematic's fine for what it is, but they call for $40/ea resistors, 
probably special order from a distributor. (VISHAY VHP-100 0.1%, ~0 ppm 
tempco, 5 of 'em) which I would like to avoid the expense of...but you 
can get Xicon 10ppm (288-0805 series) ones for <$1 from stock.

Beyond the basic app note is getting an accurate voltage (10 V?) 
referenced to the low accuracy LTZ1000 (it's extremely stable, but not 
very accurate). Again, the app note would have you use a custom 
resistor array (and even that won't get you accuracy, unless special 
ordered, custom matched to each LTZ1000 - $$$$).