The simplistic Salas low voltage shunt regulator

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I wrote just a few posts back that the 1.2 for lower phono B+ and other apps like +/-15V will have a JFET cascode main CCS tail and will be beta tested. I haven't shown a schematic because I don't know how long it will take and what the changes may be.
 
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Magic mirror and wishful thinking

There is a V1.2 waiting to be tested though

That one is the general line, I am afraid of oscillations. Its to be tested and tweaked soon.

I miss 2 parts and a some heatsinking, got to meet a busy mate to get those, before hitting the perfboard. Meantime I got a bunch of LT Spice models from Iko (thanks man!) and looked a bit on its theoretical performance, also I applied theoretical compensation & termination. It looks responsive on paper to what I had in mind to do with the soldering iron. I thought of terminating with a few uF PP and adding an R series (Zobel) as I do in the simplistic HV. That would save shopping for this or that specific esr electrolytic and its whims with age and ambient. Fixes it for termination, and gets rid of possible Cout big chemical cap's subjective signature. Now, how close those models are to the bugs and the wires that I am going to stick on that Swiss cheese board, only cosmic gurus know.:D Encouraging indications non the less, but the proof is (as always) in the pudding.:mischiev:

Anyway. The following captures represent loop phase margin, rejection and output impedance.
 

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diyAudio Chief Moderator
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Use a LEDS CCS V1.0 schematic. You just need to use low R1 for a current at least +20% of your (substantial) 400mA load. Depending on your LED Vf you must have 5W loudspeaker crossover style sandcast resistors maybe 3R3 or 4R3. The voltage across them divided by their value will give you the actual running current. Use 3K3 trimmer in the Vref, adequate sinking, and you will be ready.
 
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