19 Jun
2009
19 Jun
'09
12:24 p.m.
All of the early datasheets " TALK " about the 723 being used as a
switcher. TI, Fairchild, and Intersil actually have a switching circuit.
Philips, Signetics and SGS Thomson do not have a switching circuit on the
datasheet. SGS Thomson has an internal schematic of the 723.
Best regards, Steven
Incidentally, the 723, as I am sure you know, is a 'regulator building
kit' consisting of a reference voltage source and an op-amp in one
package (OK, that's a slight simplification...) It can be wired as either
a linear regulators (op-amp as the error amplifier, possibly driving an
external pass transistor) or a switcher.
I've heard a rumour that early 723 data sheets only show it as a linear
regulator, the designers didn't realise it could be used as a switcher.
After it started getting used in the latter configuration, example
circuits were added to the data sheet. Does anyone have an early 723 data
sheet which doesn't show a swtiching regulator circuit?
-tony