The simplistic Salas low voltage shunt regulator

[Salas]

Does anyone know if SSLV BiBs have been used for powering a BoZoS, +/-60 V @ 80 mA? Can it be done, is it recommendable?

Best regards
Staffan

They can do it when exchanging the JFET tail of the 3-4 LEDS with a 15K 2W resistor and the BC550/560 error amp BJTs with BD139/140 or better. I.e. lower Cob, higher hfe, higher Early voltage. If adequate VCEO TO-92 like BC546/556 is preferred, some dissipation aid should be provided for long term reliability. That's the technical part to meet the output voltage and dissipation spec you seek.

 

[stajo]

Thanks Salas. What base schematic are you refering to. This?

How do you think it would compare to the original?

PS. I guess I will be using one +/- PSU for both channels so that makes 160 mA

 

[Salas]

You asked for BiB. That is the pet name for SSLV1.1. There is full instructions pdf in its "builds and fairy tales" thread.

 

[stajo]

I tried to read up a bit. Is this how you mean? The BC546/556 part, what was that substitute for?

 

[Salas]

Not the LEDS, their CCS change to 15K (delete Q102/108 R108/208, put the 15K from R102/202 node to gnd).
Q104/204 are the BJTs to upgrade for higher Vceo and dissipation. Correct.

 

[Salas]

*You noted 610 wrongly, its 9610 on the positive side and 610 on the negative. Its clear in the guide's BOM.
(MOSFETS symbols have source pin semiconductor sex arrows pointing the other way than BJT symbols emitters).

 

[stajo]

More correct? What do you think about performance for the application?

 

[Salas]

Yes, its good now. R103/203 should be 18K 1W, the trimmers 5K for 60Vout.
Your electrolytics should be 80V and you will need 70V raw DC level.
It will be bit worse in performance than lower voltage standard 1.1 but better than the Zeners and series pass element one.

 

[stajo]

 

[Salas]

Q106 is a PMOSFET IRF9530, don't mind the BJT symbol. Q206 is IRF530. Use about 3.5mA IDSS for the K1117GRs.

 

[stajo]

Thanks. If I would go for 65-67 VDC in and 55-57 Vout, since dual 24 V trafos is kinda more common then dual 25-26, what do I adjust?

Edit: I meen am I ok w above components and just adjust trimmer?

 

[Salas]

Better use R103/203 15K 1W in that case.

 

[AndrewT]

Q102 (jFET) should not have a 15k in the source lead.

 

[Salas]

It must be substituted altogether by it because of its VDS max and dissipation limitations at Stajo spec voltage level. I.e. all he shows red boxed in post 6107 gets deleted and replaced by 15K 2W.

 

[stajo]

So out of curiosity, if I would P2P the PSU along with the audio circuit, should I choose another version of SSLV instead?

And, if using one pos/neg SSLV per stereo BoSoZ, do you think should I keep R16-17/C3-4 RC or skip/replace it?

Or should I then use one pos/neg SSLV per channel?

How would you have done?

 

[Salas]

No, 1.1 discussed offers itself for a less troublesome p2p, more secure against layout oscillations than some other versions.

Not sure about the local RC cell, it may be beneficial to the audio part for more reasons than the obvious extra filtering. Listen with it and the new PSU before attempting to delete it so to have some real comparison.

 

[PreSapian]

Hi, im planning on building a 2chassis dac of the latest peter daniels circuit with salas shunt psu in one box with dc out umbilical to the box with dac.

Well my simple question is, can i power additional lm317 regs from salas without disrupting the performance of the main output voltage of the shunt reg?

 

[Salas]

They have been powering Buffalo with extra local regulators, other DACs with TL431s and the like. Each application has its own quirks though. Still there is not a bad record with driving post regulation.

 

[PreSapian]

thank you, Salas.

 

[lykkedk]

5 Vdc for Raspberry, squeezebox, etc... 1-2Aamp.

Hello...

I would like to know, if there is any build of 5vdc output (1-2amp.) for the shunt -reg. ?

I have tried to find it, but there are so many comments, that i find it hard to see.

I am looking for building a new PSU, for my raspberry and DAC.

thank you / Jesper.