Filling in discrete supply values

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There are some incomplete discrete regulators schematics I have seen on an Audio-Gd DAC ad that I would like to use.

Unfortunately my limited knowledge does not allow me to fill in the active or passive parts values.

Perhaps someone can do that? I would be very grateful.

Audio-Gd is a very serious audio company, so I guess the choice for these regulators geometry must have been very careful.
 

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Not all that careful, two of the bridge rectifiers are clearly drawn incorrectly!

Without knowing how much current is to be drawn on each rail it is impossible to size the current sources (This is a set of shunt regulators at heart), and without knowing what the minimum load is you cannot size the shunt section (Which dissipates MORE power at lower load current).

Frankly this reads to me as complex for the sake of complex, and not even very interesting (Basically 6 sets of essentially the same current source plus shunt reg topology), but come on 48 transistors for a ******** power supply??!.
 
Indeed, and if you don't know enough to design the details, then what makes you think you know enough to design the bits that are not on the schematic?
Even if it was the best regulator in the world, and even if the schematic was fully detailed, you would have half a design.

Layout really, really matters when you want high performance, and if you don't get that right then you may as well be using LM317s or 7815s or the like, because the performance will likely not be improved by adding more parts to a poorly thought out board layout.

Regards, Dan.
 
Not all that careful, two of the bridge rectifiers are clearly drawn incorrectly!
Which might have been done on purpose ;)
No Tech would be fooled by that, of course, but it would serve to separate the Men fom the boys ... what is exactly happening here :cool:
Frankly this reads to me as complex for the sake of complex, and not even very interesting (Basically 6 sets of essentially the same current source plus shunt reg topology), but come on 48 transistors for a ******** power supply??!.
I guess there is people who has no clue, but confuses complexity with quality, so that makes them a (commercial) target :cool:
 
Well, well, well, I didn't want to stir up things so much.

There was no agenda over this, just curiosity, and perhaps a chance to learn. That's all.

Of course the original diagram might be drawn wrongly or just for fun. That doesn't mean someone could or would be willing to work on a discrete supply.

Unlawful? Really, DF96? AFAIK that design looks like open information, and even if patented you can use it for your personal purposes or things like that.

The only logic, Jan, is that in times of chip regulators, linear or not, having a discrete regulator must have a reason for it, particularly on a DAC. It would be interesting if someone could comment about it.

It was not the "complexity" that caught my attention, as what's inside chips is even more complex usually. Complex certainly does not mean necessarily better, just complex.
 
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Question:
in times of chip regulators, linear or not, having a discrete regulator must have a reason for it,

Answer:
I guess there is people who has no clue, but confuses complexity with quality, so that makes them a (commercial) target

By the same token, lots of people confuse simplicity with low quality and despise VERY good performing chipamps.
Same thing.
 
It is, as already identified, cascaded shunt regulators. Four similar blocks. Shunt regulators require, opposite to series regulators, detailed knowledge of the load. Else, the power loss becomes excessive.
Without intention to sound harsh, I will say that the chance of success with a circuit you understand and master is much higher than if you choose for a circuit that is somewhat obscure and you try to guess how it should work.
Without knowing your load characteristics I cannot "fill in the values". Even knowing the load characteristics it is not trivial.
NB: I do not believe you have copyrights/design-protection on electronic circuits as such. If you have a surprising technical effect the circuit may be patented. I doubt it is the case with this circuit.
 
Thanks, that is a very legitimate argument to stop with this idea of mine. That this design was a shunt I did know, but I hoped that it would avoid the "problem" I see in shunt regulators.

There are apparently very good shunt regulators on this forum, particularly the one designed and perfected by Salas, but as you well say shunt regulators are tweaked according to the load, and even so I think they waste quite a lot of voltage and current.

Not much more to say. Better stay with the regulators I know, discrete or chip, or a mix of them.
 
carlmart said:
There was no agenda over this, just curiosity, and perhaps a chance to learn. That's all.
You want someone to spend many hours reverse-engineering a circuit which contains (possibly deliberate) faults just to satisfy your curiosity?

carlmart said:
Unlawful? Really, DF96? AFAIK that design looks like open information, and even if patented you can use it for your personal purposes or things like that.
In the EU it is lawful to reverse-engineer a product for the purposes of making another product which interfaces with it; there is a specific exemption from a general ban on reverse-engineering to cover this. It is not lawful to do so for the purposes of making a clone. Of course, private study is OK - but private study would surely mean you reverse-engineering it yourself?
 
Perhaps my curiosity was not only mine. You insist on making this matter sound something selfish, stupid or criminal, all at the same time. If you do not approve of something, you made your point. Now please backoff.

Fortunately I do not live in the EU to care what is lawful or not there. As no one seems interested or shares my curiosity, this discussion seems pointless.
 
Perhaps my curiosity was not only mine. You insist on making this matter sound something selfish, stupid or criminal, all at the same time. If you do not approve of something, you made your point. Now please backoff.

Fortunately I do not live in the EU to care what is lawful or not there. As no one seems interested or shares my curiosity, this discussion seems pointless.

As the principles of law concerning technical constructions interest me, I took a quick look around. You can safely come to Europe is my conclusion. You only do what any intelligent technical minded person would do - wonder how this existing technical design actually works? An intellectual activity that has brought richness to the Far East but also been applied in Europe after the Second World War.
The heavily disputed concept of legal boundaries for reverse engineering are mainly concerned with commercial benefits from reconstruction and copying of complex constructions such as software programs.
Reverse engineering in legal perspective is in-between copyright and patent protection. If a valid and pertinent patent exists, commercial use is not permitted. Technical constructions normally rely on patent protection (if any).

Copyrights are less well defined and typically relate to constructs that include so many characteristics that it would be improper if an existing construct would be copied, for commercial purposes, more or less in all details to serve a purpose that can be served in a myriad of other ways.
Examples: Books, music, aesthetic outlines etc.

8 transistors in a circuit where the function of at least three transistors is trivial will hardly qualify for the complexity of copyright. If no patent is valid, even commercial use may be permitted. But, as I have said before, you may be disappointed even if the circuit is understood in details, including dynamic properties. This circuit probably works well in a particular context but is hardly suited for general purposes.

Remain curious and analytic, this is the nature of an engineer.
 
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