Simplistic MosFET HV Shunt Regs

diyAudio Chief Moderator
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Even 10V DC in-out is enough for this regulator's main CCS to be stable. With 250VAC Tx and a solid state rectifier bridge you should reach well over 320V raw DC input. How to set CCS mA and output voltage with circuit's trimmers and how to pre-test on a proper dummy load even, that's all in the pdf instructions.
 
Even 10V DC in-out is enough for this regulator's main CCS to be stable. With 250VAC Tx and a solid state rectifier bridge you should reach well over 320V raw DC input. How to set CCS mA and output voltage with circuit's trimmers and how to pre-test on a proper dummy load even, that's all in the pdf instructions.
Thank you Salas! Where is the pdf file? I only parsed the first couple of tens pages of the thread :)
 
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Yes, its the same transistor but from different manufacturers. Also mentioned in the guide's BOM "Q4,Q5=KSA1381 Fairchild (2SA1381 or ''SA1381'' Sanyo FBET)"

A bigger C2 filters the Vref's noise better but on the other hand it takes more time to charge. That creates longer time stress between Vin & Vout. If you use solid state bridge rectifier that develops Vin instantly better keep C2 at its 10uF standard.
 
A bigger C2 filters the Vref's noise better but on the other hand it takes more time to charge. That creates longer time stress between Vin & Vout. If you use solid state bridge rectifier that develops Vin instantly better keep C2 at its 10uF standard.
Hi Salas
what about using an electrolytic cap + a film bypass? like 10uF+100nF, this using a tube rectifier.
 
Hello, I have PSU for a field coil fullrange speaker. Best sound using 20uF+10H+20uF (CLC) after the bridge.
Load is 77V @ 154mA.
I have a good sound using quality parts, but I wonder if improvement is possible further adding an SSVH2 reg.
How could I increase the current above 110mA., and lower the voltage below 100VDC.?
Anyway I must improve something, as I have a loud bump on that expensive cone, when I power it off.
Thanks in advance, Jordi
 
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Are you sure, that SSHV2 shunt regulator is the best option?

IMHO the main problem (bump) due that field coil is paralleled last C, so at the beginning practically shunted it.
The charging current (which is minimally added to used DC current, so in case of resistive load almost static) firstly magnetizing the field coil, than charging the last C. This is produces overloading in first L, so there are swinging.
The -last- C//L tank is resonant, due it there are swinging too, till field coil magnetizing up.

If you use SSHV2, in the first time the CCS starting magnetize the coil (which is -at the beginning- practically shunting the SSHV2 parallel regulator) with full CCS current.
The voltage will be firstly high (almost B+), then lower, about Iccs*DCRcoil (with some ringing).
When coil magnetized, the regulator will working as regulator.

CCS magnetizing coil.jpg