SSR01 questions

[peranders]

This is the wrong type. It's a low voltage type, 1.24 V but you can still use it. Take 10k + 10 k as feedback, then you'll get 2.5 V from it. You may also check the datasheet for the IC. Did I suggest this reference or have I written the wrong article number?

[MacMiniHiFi]

I will try to find out the origin of this component. I don't think it is a problem in your end as I did not have to buy any new components for this build (the component list is pretty much identical to the one for the JSR03). However, I don't even remember having ever bought this particular reference.....
Thanks.
Nic

[peranders]

This part will work if you set the reference voltage to 2.5 volts.

[MacMiniHiFi]

Ok. Your BOM is correct.
I changed the 1.24V reference with a pin compatible 2.5V ref (TL431CLP) and now everything works (I think). It is still a mystery why I have LMV431 v-ref's around and it might explain a few JSR03 that I never got to work!
Thanks for the support that lead to the solution.
Nic

P.S. I'm not sure exactly how to change the reference to 2.5V so I tried the swap first.

[peranders]

You can change the reference voltage by help from a voltage divider between the REF and anode and REF and cathode. This written in the text for JSR01 and also at the of the datasheet of LM431. There is also some other difference between the regular 431 and the low voltage type. I don't remember what but I think it was the current range.

[Monello (MacMiniHifi)]

Sorry P-A, but I had to re-register to get in.
What is the recommended pre-regulation before the JSR and SSR super regulators? Just rectification or maybe something more sophisticated like high-frequency filters etc? Schematics for a (semi)Newbie would be welcome.
Thanks Nic

User Monello is deleted. /Admin

[peranders]

What was the trouble to log in? Both of "you" have been logged in today. I'll prefer one user per person.

The super regulators need 2-3 V more in than the output voltage and with a preregulator you'll need 4-5 V at least. Examples how the circuits can look like can be found in the QRV08, JSR04, JSR06 and QSXPS.

[Ekke]

What these 2.2k (R1...R13) & 10k (R5...R14) values are? Schematic have only 1k & 47R for those? Have I missed some documentation? I deleted C14 & C15, won't be using sense, so it's ok?

EDIT: 5V version...

[peranders]

I must fix this. This is something when you create the BOM. I'll get back to you.

[peranders]

Ignore the "LibRef" column.

[Ekke]

Thanks, makes sense with the schematic.  :-)

[Ekke]

Is there any option for bc556c? Or a source for those? Can't find those from Digikey/Farnell/Elfa/eBay..  :|

Is bc557c ok? Same but lower voltage rating?

[peranders]

BC557C is OK if you have max 30 V in. "B" is also OK.

[qusp]

well, I must say these are great little regs, using them to feed a PCM1794A dac and sound seems to have quite noticeably blacker background. 5v reg is stable under load at 4.975 and that is to be expected duie to using a couple of 5% resistors instead of 1%. this means nothing anyway as it is stable and quiet. so at the moment sense wires are shorted under the board, but i'm going to wire them up tomorrow, should the ground and u sense wires shield be grounded at both ends or just floating at the target? obviously the wires should be the same wire used for the load correct?

using silmic II, nichicon FG and vishay MKS, opamp is 825, red LEDs etc. everything pretty much stock on these 2

will I kill the regs using them without a sink at low voltages? the dac is in a cardboard box at the moment for a few more days and I have some slabs of copper coming for the RFB03, but at the moment running with 9vdc in and 5vdc out. not going to be running it much until its cased anyway, but thought I should check in case I kill them while I wait for these bits to arrive. will be using the case for the regs and the slab for the rectifier. going to do something similar to the low noise/low power modified one for preamp

[peranders]

You will kill the regulator if it gets too hot. It's as simple as that. Too hot is above 110-120 degrees C. It's also about life time. High temperature will shorten the life time.