Super Regulator, collecting the facts

[mrfeedback]

Originally posted by Fred Dieckmann
"Not much, I suppose. <100 mA?"


>100 mA DC. The regulators will work better with load currents above 100 mA
than low current loads like 10 or 20 mA.

There is an extremely simple explanation for this for anybody who knows a little electronics.....

Anybody?

Mainly a question about how much this kind of regulator circuit improves sonics of what kinds of line (or other) stages, and with respect to other regulator techniques.
Out to what power is easily achievable ?.

Eric.

[peranders]

Originally posted by Fred Dieckmann
"Not much, I suppose. <100 mA?"
>100 mA DC. The regulators will work better with load currents above 100 mA
than low current loads like 10 or 20 mA.

There is an extremely simple explanation for this for anybody who knows a little electronics.....

Anybody?

Not very suitable for a normal transistor amp then or a couple of opamps?

[Christer]

Originally posted by Fred Dieckmann
"Not much, I suppose. <100 mA?"


>100 mA DC. The regulators will work better with load currents above 100 mA
than low current loads like 10 or 20 mA.

There is an extremely simple explanation for this for anybody who knows a little electronics.....

Anybody?

Higher current means higher gm of the pass transistor means
higher loop gain. Culd that be what you mean?

Originally posted by peranders

Not very suitable for a normal transistor amp then or a couple of opamps?

A dummy resistor to ground will solve that. It's just a regulator,
not a nuclear power station.

[Fred Dieckmann]

Preloading regulators with a resistor is a VERY common technique and written about in TAA probably 15 years ago. This circuit was origionally developed as a regulator for low current preamp type circuits! Are Jan, Andy, and I the only ones that read all the TAA articles?

Christer,
Not quite on the guess, but you getting warmer*. The other way to lower the output impedance instead of increasing the amount of negative feedback (or increasing the open loop voltage gain, that is) would be to do what?


Peace,
Fred

*So is the regulator at increased current loading now that I think of it....

[Fred Dieckmann]

"Fred, where does the picture come from?"

Sorry wrong schematic......

[Christer]

Originally posted by Fred Dieckmann
Preloading regulators with a resistor is a VERY common technique and written about in TAA probably 15 years ago. This circuit was origionally developed as a regulator for low current preamp type circuits! Are Jan, Andy, and I the only ones that read all the TAA articles?

I don't know if I've read them all, but I suspect not, which is
why I asked about the origin of that schematic.

The other way to lower the output impedance instead of increasing the amount of negative feedback (or increasing the open loop voltage gain, that is) would be to do what?

Let's see, the output impedance of an emitter follower is
Vt/I if ignoring the source impedance, so higher current means
lower open loop output impedance and, needless to say,
lower closed loop output impedance. However, this is just
the other side of the same coin as the gm stuff, so maybe
that's not what you are after either.

Peace,
Fred

[Damon Hill]

Where is the MOSFET version written up? How does
it compare with the original version?

I'm having some trouble keeping up with the BJT
variations.

--Damon

Hafler SE100 all-JFET preamp with Jung SR using AD797
working on bench supply using some flavor of Jung SR

[Fred Dieckmann]

"Let's see, the output impedance of an emitter follower is Vt/I if ignoring the source impedance, so higher current means lower open loop output impedance and, needless to say, lower closed loop output impedance.

Just det! Den skall inte spela någon roll spänning förstärkas

Peace,

Fred

[Christer]

Originally posted by Fred Dieckmann
"Let's see, the output impedance of an emitter follower is Vt/I if ignoring the source impedance, so higher current means lower open loop output impedance and, needless to say, lower closed loop output impedance.

Just det! Den skall inte spela någon roll spänning förstärkas

Yes, I realized later the gm wasn't very important, since it is
only the closed-loop gain that lowers the output impedance.
Anyway, this was interesting. I hadn't thought about this
before you challenged us with the question.

[Christer]

Köttbullar is swedish for meatballs. Isn't that the swedish chefs
specialty? It's been a long time since I watched the muppet show,
though.

BTW, the swedish chef doesn't sound very swedish at all to
swedish ears, but I recently heard the story behind this
character. It turns out there was a swedisch guy from a part
of Sweden called Dalecarlia (Dalarna in swedish) who worked
in the US. People from Dalecarlia sound a bit funny even to
many of us swedes (funny in a nice way, I should add).
Apparently he had quite a strong such accent also when
speaking english which people found so funny that they decided
to try imitating his way of speaking english when creating the
chef. I suppose that is the reason he ended up as a swedish
chef, and not some other arbitrary nationality.