Super Regulator

AX tech editor
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Maakt mij niet de brutale :confused:

I have taken all the measurements as per the whole design and discussion yet it remains at 13vdc.

I have installed a trimpot in place of R6 to adjust it spot-on and no luck.

Tried 2K2 with 5K45 ratio and the 1K with 1K4 ratio and no luck. The Zener is a 12v unit and I have confirmed it.

On pin 2 I get 5.7 and on pin 3 I get 6.3vdc

Supply voltage is 36vdc
Load is a Pass XLmini filter board for 24vdc.

What is your ref part?

Please show measurements on all opamp pins, and the two resistor values with which the measurement was done.

Jan
 
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AX tech editor
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All these resistors will work, but the higher values will a) create more noise and b) influence some circuit voltage values.

Not critical but midranges probably better.

The regulator is basically a feedback amplifier with the ref as input. So, the higher the ref, the more loop gain* and thus the tighter the regulation.

Obviously, ref cannot be higher than Vo. Within that window, whatever floats your boat, but make sure the ref is reasonably stable and low noise.

*The loop gain is also dependent on the attenuation from the two feedback resistors, and a higher ref allows less attenuation. It all hangs together ;-)

Jan
 
AX tech editor
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1 = 0vdc
2 = 5.7vdc
3 = 6.3vdc
4 = 0
5 = 0
6 = 1.7vdc
7 = 13vdc
8 = 0

Resistors - R7 = 1K & R6 = 1K4 - R6 side is 12.5vdc and resistor junction at 5.7 vdc

12V Zener - A = 13.5 & K = 1.4vdc


OK, that's helpful. The circuit seems to work basically, the +inp = 6.3 where I expect 6.9 from the ref. but clearly the protection diodes at the input are engaged to protect the opamp. I assume you use a 6.9V ref. You mention a 12V zener but that is the zener at the output of the opamp, not the ref diode, correct? If that is so, we see that the opamp can't get the output high enough because in this scenario the 12V is too high (it's OK for 24V). If you had used a lower value zener you would have seen an output value of 2.4 * 6.9 = 16.6V with the resistor values you used.

From a 6.9V ref to 24v requires a resistor ratio of (24-6.9) to 6.9, is about 2.6. So 1k and 2.6k should give you 24V with a 6.9v ref.

It seems like you used the 12V zener value for your calculations instead of the actual 6.9V ref diode. Have I got that right?
What opamp did you use?

Jan
 
I run a business and don't have too much time on my hands to read writeups... got to get the work done.

I live in rural South Africa... a 12v reference is probably going to take a week to 10 days to order and get delivered. For the interim, I installed an LM317 regulator in place of the Supereg. The client was informed about this.
 
Interestingly, I had a similar question: what are the values of R6 and R7 to obtain +24VDC? So, I just read this and so it appears to me that for a +24VDC output, using just the positive side of the board, and with +24VDC input from the supply voltage , this should work out to be R6= 2.6k, R7=1k.
I so wish that there was a chart for people like me who struggle even with the simplest math.
 
AX tech editor
Joined 2002
Paid Member
I run a business and don't have too much time on my hands to read writeups... got to get the work done.

I live in rural South Africa... a 12v reference is probably going to take a week to 10 days to order and get delivered. For the interim, I installed an LM317 regulator in place of the Supereg. The client was informed about this.

You already have a ref of 6.9. You just have to adjust ONE resistor.
Reading The F Manual is incredible effective, especially if it s less than one page. Most professionals know that.
But if you have all the time you need and don't mind to restart several times, hey, whatever floats your boat.

But to conquer yourself rather than the world, it might help to realize that you just spend time and money and failed a project because you didn't read one page.
Worse, for me, I spend over an hour of my precious free time trying to help you out, for the cat's whiskers.

Jan
 
Last edited:
AX tech editor
Joined 2002
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Interestingly, I had a similar question: what are the values of R6 and R7 to obtain +24VDC? So, I just read this and so it appears to me that for a +24VDC output, using just the positive side of the board, and with +24VDC input from the supply voltage , this should work out to be R6= 2.6k, R7=1k.
I so wish that there was a chart for people like me who struggle even with the simplest math.

Please let me know which is the part you are struggling with and I will see how to improve it:

https://cdn.shopify.com/s/files/1/1006/5046/files/Superreg_customizing_r2.pdf

Jan
 

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Sorry but this ONE resistor you are referring to is extremely vague... you hammered on the REFERENCE making me think I confused it with the regular Zener. I have read the manual... I have printed it out. But I don't have time to decipher sarcasm. Leave it at that. Thank you.

You already have a ref of 6.9. You just have to adjust ONE resistor.
Reading The F Manual is incredible effective, especially if it s less than one page. Most professionals know that.
But if you have all the time you need and don't mind to restart several times, hey, whatever floats your boat.

But to conquer yourself rather than the world, it might help to realize that you just spend time and money and failed a project because you didn't read one page.
Worse, for me, I spend over an hour of my precious free time trying to help you out, for the cat's whiskers.

Jan
 
Sorry but this ONE resistor you are referring to is extremely vague...
Think of it in terms of the LM317 which you have used. The LM317 uses a 1.25V reference and then a two resistor divider to produce an output that is a multiple of the reference. The multiple is determined by the values of the two resistors in the divider.


The super regulator uses a different reference which might be 6.9V in your case. Then a resistor divider is used to produce a fraction of the output voltage on one of the inputs of the op-amp. The reference is fed to the other input of the op-amp. Then the output is a multiple of the reference voltage. The multiple is determined by the values of the two resistors in the divider.


If the output is half what you need then double the multiplier. For example, increase the upper resistor in the divider or lower the lower resistor in the divider to produce twice the multiplier (or ratio) value.
 
Well, I built the B1 Korg Pass design, and it requires +24VDC... I have a regulator that will provide that +24VDC, BUT I want to add this 'super regulator' to it... If I have an output of +24VDC (it is adjustable BTW) from my regulator, to the 'super regulator', what are the values needed for the 'super regulator' resistors R6, and R7, and maybe the zener diode?
 
Perhaps the attached spreadsheet would be helpful. I have used the resistor values from the store schematic and varied R6 over the E12 series.


Of course the op-amp shown can not operate at the higher voltages. And other components (Zener, capacitors) would need adjustment.
 

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AX tech editor
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Perhaps the attached spreadsheet would be helpful. I have used the resistor values from the store schematic and varied R6 over the E12 series.


Of course the op-amp shown can not operate at the higher voltages. And other components (Zener, capacitors) would need adjustment.

Very good, including R16 as well!

I will ask Jason to put it in the store documentation.

Edit: how about a low voltage version with a 2.5V reference voltage?

Jan