Re: Re:_[sdiy]_+-12V_supply

[Roman]

you're right, telling that something sucks may be offending to milions of people using it.
So to make it more specific, here's my explanation why they suck:
- it would be a bit tricky to achieve +/-1mV accuracy from them
- they have considerable load and line regulation (not a big problem if you have constant load and stable power line)
- they have considerably high quiescent current, not acceptable for battery operation.

fair enough?
Roman

---- Wiadomość Oryginalna ----
Od: James Patchell <patchell at cox.net>
Do: synth-diy at dropmix.xs4all.nl
Data: Fri, 14 Jan 2005 16:45:06 -0800
Temat: Re:_[sdiy]_+-12V_supply

> Making blanket statements about parts sucking always cracks me up.  Since 
> the 78xx/79xx regulators are the biggest selling regulators, that either 
> means everybody is stupid, or the parts must have true value.  I have run 
> into a few engineers who felt the same way.  After fixing their mistakes, 
> the parts have always worked flawlessly.  There are applications where they 
> will not work.  I think I have only encountered one of those in 30 years....
> 
> At 07:02 AM 1/14/2005 -0700, Scott Gravenhorst wrote:
> >=?iso-8859-2?Q?Roman?= <modular at go2.pl> wrote:
> > >if putting 723 instead of 7812 is an overkill, how would you call
> > >someone who made 1.5A power supply using regular opamps,
> > >darlington transistors, lots of other components, and 10ppm/K
> > >reference IC, where LM317/337 would be more than enough?
> > >
> > >You're right, a crazy maniac.
> > >But I just wanted it so bad.
> > >
> > >BTW, IMHO 78xx and 79xx suck
> > >
> > >Roman
> >
> >Hmm.  Well, everyone is entitled to an opinion, I use 78xx and 79xx
> >and I don't have problems with them.  I just don't hear the noise
> >that they're supposed to make.  Not only do I use these nasty 3
> >terminal regulators, I use them with AC wallwarts and halfwave
> >rectifiers.
> >
> > >
> > >---- Wiadomość Oryginalna ----
> > >Od: "Roy J. Tellason" <rtellason at blazenet.net>
> > >Do: synth <synth-diy at dropmix.xs4all.nl>
> > >Data: Thu, 13 Jan 2005 20:50:36 -0500
> > >Temat: Re: [sdiy] +-12V supply
> > >
> > >> On Thursday 13 January 2005 06:55 pm, Chris CROSSKEY wrote:
> > >> >  Toss out the 7812/7912 and use a 723 on each side with a big bypass
> > >> > transistor.....
> > >>
> > >> Why,  if the simpler setup will do what you need?  Did I miss 
> > something there
> > >> that indicated a massive current draw requirement or something?
> > >>
> > >
> > >
> >
> >---------------------------------------------------------
> >- Where merit is not rewarded, excellence fades.
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> >- The media's credibility should always be questioned.
> >- The only good terrorist is a dead terrorist.
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> >
> >-- Scott Gravenhorst | LegoManiac / Lego Trains / RIS 1.5
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> 
>          -Jim
> ***************************************************************
> http://www.oldcrows.net/~patchell
> 
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>