723 IC origins / was Re: Hardware Hobbyists vs. Emulator Jockeys

[Brent Hilpert]

blstuart at bellsouth.net wrote:
> >>
> >> I just checked what I have.  My 1977 Voltage Regulator
> >> Handbook doesn't list it at all.
> >>
> >> My 1980 Linear Databook
> >> includes a couple of switchers among the typical applications.
> >> That would suggest such a data sheet would have to be
> >> around 1978 or 79.
> >
> > The earliest example I have at hand for the 723 is the manufacturer's schematic
> > for the Wang 520 calculator. The power supply page with two 723's on it (used
> > just in linear mode), is dated early 1971. Perhaps the earlier handbook was
> > from a manufacturer that didn't 2nd-source it.
> 
> It was a National book, but I can believe that it could
> well be incomplete.  That's why I equivocated and said
> it suggested a time frame.  The existence of it in these
> earlier systems clearly moves the lower bound.

Funny that it wouldn't even be mentioned, perhaps the chip was old enough by
that time that it got left out of a current-techniques handbook (as opposed to
a databook) in favor of newer stuff.