Vreg identification

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Found this one in a zip file on this forum:

Reg.jpg


But cant find where now,anybody recognize it?
How much current can it take?Is it the LM317/337 that sets the limmit?
Is it tested.
 
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Ryssen said:
Found this one in a zip file on this forum:

.........................

But cant find where now,anybody recognize it?
How much current can it take?Is it the LM317/337 that sets the limmit?
Is it tested.


voltage is up to 1,25(1+R3/R1) , decreased little via 1E on output ;

shunt positioned darlington thingies on outputs are sort of cap multipliers,or shunt ripple eaters......... if you wish.......... ;)

current- LM317/337 boundaries........

I have no any further info- where ,when,tested or not.........
 
Yes, should work.
But such an errorous schematic is not a very good starting point for a good regulator, also wouldn't it be nicier to build a complementary regulator with xx337 and PNPs rather than going positive regulator mimic negative regulator?
I would not go to such tricks just because someone posted a schematic full of mistakes, he probably never built one.

regards
Adam
 
Hi,
you might be able to get upto half an amp out of it.
The shunt reg can temporarily be omitted and the circuit operated as a series only regulator.
Then add in the extra components.

If output voltage=20V, then min input voltage ~=23V.
Add on transformer regulation and twice the mains tolerance and ripple and the maximum input voltage will be ~=30Vdc.
Input to output Vdrop ~=10V and @ 500mA, Pd ~=5W. That needs an enormous sink, but just about possible.
200mA to 300mA might be a more realistic maximum output.

Correct the errors as mentioned earlier.
 
Add on transformer regulation and twice the mains tolerance and ripple and the maximum input voltage will be ~=30Vdc.
So minimum in/out is 10v then.
Does this apply on a series regulator to,(that needs 3volts over the passelement?)

A litle OT,can I use a hi effect mosfet as passelemt in a Jung type seriesregulator for higher effect like for a minialeph?
Does the mosfet requier less voltagedropp than a BJT?
 
Hi,
the minimum Vdrop across the regulating transistor (BJT or FET) must be exceeded when mains voltage is lowest and output current demand is highest. But the ripple in the supply must also be taken into account.

The worst dissipation of the regulating transistor is with the mains voltage at highest level and demand also highest. Again ripple is high for this operating condition.

The worst case for the smmoothing capacitors is usually mains at highest and demand at lowest, worse if load is temprorarily disconnected. Ripple can be tiny this time.

You may find Min Vdrop value between 0.5V and 2.5V depending on topology and devices.
 
I'll just list the positive side:
C1 & C7 to JP1 #2
Then star ground all others to JP2 #2
One star point
R3, C3 & C11
An other star point
C9, C5, R8, R15, C17 & C15
A third star point
C19
JP1#2 remains connected to JP2#2

But other people with more skill might have better ideas.

I still like the idea of two positive regulators and so does Walter Jung.
 
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