legg wrote:

Splitting hairs, but the Nat Semi original regulator part numbers were
LM104 (204, 304), LM105 (205, 305), 109, 117, 120 etc. The 78xx
nomenclature (and pinout) were Eairchild (uA78xx).

Understood. I started with the 78 78 series first, because
they are more common, today, and I hoped to make some models
I could throw into practical simulations. But I intend to
look into the LM140 series, too.

You're refering to the 'Widlar diode' that was developed and employed
in these parts (inventor Robert Widlar). There should be plenty of
stuff out there, as it's in most integrated circuit design course
notes. Check some of Robert Pease's articles - he assumed the role of
'emperor' or policeman of band-gap' reference implimentation at Nat
Semi.

Thanks for the leads.

The published schematics were never intended to be anything more than
conceptual, as the cell device characterisrics and scaling are part of
basic reference function and temperature compensation.

Trying to go from the simplified schematics to a working
spice model is part of the fun. I found what I think are an
error and a scaling omission on the LM79XX schematic before
I got it to work, at all. But it is about twice as
complicated as the LM78XX schematic.

--
Regards,

John Popelish