[723 regualtor as a swticher]
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.
You want to go back much further than that. DEC were using the 723 in a
swithcing regulator circuit in 1972 (the date of my 11/45).
-tony