723 Switcher; was Hardware Hobbyists vs. Emulator Jockeys

Scanning steven.alan.canning at verizon.net
Fri Jun 19 11:24:13 CDT 2009


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



More information about the cctalk mailing list