> I have a desire to build a general purpose lab-style power supply =20
> using multiple 317s.  Several in parallel for increased output.  One =20
> for the negative-voltage-driven current source that permits voltages =20
> below 1.25V

I've just about finished putting this together, perhaps make more

http://home.clear.net.nz/pages/joecolquitt/PSU_schematic.gif

PCB pattern can be got from Silicon Chip's Downloads section, 6/10

Maybe VG would do you a board ;-)

One modification will be an F88 and 16 x 2 LCD to display more
information than the 3 1/2 digit panel meter. The one specified for
the PSU is ICL7106-based

www.intersil.com/data/fn/fn3082.pdf

with a 200mV input. I've made a board with six DC amps for the
F88 ADCs. Nothing powered up yet, awaiting a 79L15

Joe
--=20
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