The simplistic Salas low voltage shunt regulator

[RCruz]

O... I did not read the inscriptions... What type of chip is it ?

[krivium]

Calmart, try page 429 post #4287 of this thread for Reflektor description.

Only if you can cool Q3 with TO-92 minisinks. Its a matter of dissipation for that high Vout. The others in the current mirror don't suffer as much voltage drop.

Salas, please excuse me i wasn't clear with my last question, 2sc2240 or BC639 for cascode CCS? (for Q1,2,3,4 KSA1381 planned).

After quick look at schematic, for R1, approx 23r for 30ma seems right?

[Salas]

Both are good for implementing a ring of two 2mA CCS for over 60V. R1 will be giving current as Vbe/R1. Depends on the transistor used, but 0.6-0.7V should be ballpark.

[Salas]

Originally Posted by RCruz

O... I did not read the inscriptions... What type of chip is it ?

Mini shunt reg.

[krivium]

Thanks Salas.

[Salas]

You got to run extra current for the reg itself remember, its a waster.

[carlmart]

Originally Posted by krivium

Calmart, try page 429 post #4287 of this thread for Reflektor description.

Sorry about the Reflektor confusion. I didn't know what it was.

What voltages can be implemented, in versus out, for those component values in post #4287?

[Salas]

Not more than 40V max In if you got 2SK170, no more than 30V max In if you got BF245B (470R R4 when with 245B) for J1. 34V out and 24V out respectively. 10K trimmer for R6 connected as rheostat should cover all that range. Won't go lower than about 7 Vout in both cases.

[carlmart]

The regulator looks quite flexible. No concerns about minimum or maximum currents?

Good to know about the BF245B, which I think I can get here in Brazil.

What about the IRF types? Some flexibility with them too?

I have to check which ones might be available here. In any case I think the SK170 and those IRF can be found on eBay, probably with the same JC-2 kit vendor.

[krivium]

You got to run extra current for the reg itself remember, its a waster.

Thank again Salas, planned as 3x current needed by load in reg, and 3x reg current need for prefiltering.
I asked about R1 just to be sure about calculation, not missing something from your explanation.

In any case I think the SK170 and those IRF can be found on eBay, probably with the same JC-2 kit vendor.

Be careful about SK170 at the ebay... many many fakes.
Be sure that seller accept return and cash refund and check your whole lot at arrival for Idss as you'll have to do it anyway. If off spec they're fakes so send them back.