0-30V Stabilized Power Supply

[audioguru]

Hi audioguru,

After this suggestions made by you and the others, what's the best and final circuit. By the way and what about tesseract's circuit, it seems quite simple...

Thank's in advance

The best and final circuit has been posted here many times. It uses MC34071 or TLE2141 single-supply opamps.

Tesseract never said which version he used. He said he used three high dissipation output transistors for an output up to 5A.

[akademiker]

works awesome, thank you very much!

Next on my list: Upgrade to 8A version  ;D

P.S. use PTC! They limit the output current in case of a transistor melt down

[redwire]

Nice Job, Congratulations.

[bugmenot]

Hi RedWire, this is your double sided PCB made with the toner transfer method. Soon I will make your 5A PSU version. I build the original before I see this forum... Now I will upgrade to the 5A version with samples of TI. I'll post the progress...

[bugmenot]

Again... ;)

[bugmenot]

Hi, Can Audioguru comment the modifications suggested from Ivan in the main page os the original project? I would know if I can upgrade my original project and and make it great without change the PCB. I'll change some resistors Watts too.
Please help here AudioGuru. Thanks a lot. Best Regards.

[Hero999]

I like the way you've done the silk screen - I use the same method. :D

I notice there's a track that doesn't go anywhere and another track is broken; is that deliberate or a mistake?

[audioguru]

Hi, Can Audioguru comment the modifications suggested from Ivan in the main page os the original project? I would know if I can upgrade my original project and and make it great without change the PCB. I'll change some resistors Watts too.
Please help here AudioGuru. Thanks a lot. Best Regards.

Where is "the main page of the original project"? please provide a link.
The original project had many overloaded parts including its little transformer. Its opamps operated at a total supply voltage that are higher than their max allowed supply voltage and even then the project did not have enough voltage to produce 30VDC at 3A. The main filter capacitor value is much too small.

[bugmenot]

http://www.electronics-lab.com/projects/power/003/index.html

[bugmenot]

Gi Hero999, Hehehe, there are 2 break tracks... one top and one bottom... ;D it's anxiety, but its fixed. I thought that nobody will notice... The tracks without a destination you have to ask to RedWire... I only change the bottom area for the ground... Thanks for comment.

Audioguru, the Ivan comment are in the bottom of the link of the project... Do you see?

[bugmenot]

Ah I have to say this is my first double side PCB I made, so forgive any faults... ;)

[bugmenot]

...

[audioguru]

Hi, Can Audioguru comment the modifications suggested from Ivan in the main page os the original project? I would know if I can upgrade my original project and and make it great without change the PCB. I'll change some resistors Watts too.
Please help here AudioGuru. Thanks a lot. Best Regards.

Ivan reduced the positive supply to the TL081 opamps to only 27V so they do not have a total supply that is higher than their 36V max allowed supply. Then his project will have a max output voltage of only about 22V or less.
His little 24V/3A transformer and many other parts including Q2 are still overloaded.

[bugmenot]

I am also a little confused with some connections points in the RedWire PCB...connection point 4B, 4B1, 4, 4A...etc. Can redwire give some help?  ???

[bugmenot]

So, Audioguru I understand that have more to modify in the original project. I only want to save my original project, make the mods to make it more confiable... I'll make the mods sugested from Ivan and change the watts of some resistors too with your guidance  ;D off course, hehehe. The 2N2219 in my project ahs a heatsink appropriate for this package, and I want to put a fan in the PSU, the LCD meter module has a control for a fan with a mosfet, it power the fan when the load is heavy duty, I think...  ;).
Can you describe, please, the all parts I have to modify? resistors watts, etc...
Here the pictures of my original project and the LCD module... After I post inside pictures of it ok?

[audioguru]

Hi Bugmenot,
Why not make the latest circuit? It works very well. It is not changed much from the original, all parts operate within their ratings and the opamps are available nearly everywhere.

Ivan simply reduced the positive supply voltage to the opamps then the max output voltage is low but the heating is still very high.

What about the transformer? The transformer in the original project and the one in Ivan's circuit is overloaded at max output from the project.

[bugmenot]

Hi AudioGuru, it's because the iginal PSU is already assembled and working, with this limitations, off course... And I want to make it more reliable.
I'll build the 5A RedWire version too, I already make the PCB for it and i'm waiting for the parts...
The transformer I use in the original version have a secundary of 26V at about 3-3.5A. In this PSU I don't need the 30V in the output, ok? So I can use this transformer... In really In this PSU I need less than 30V! If it is the case I  can rebuild the secondary, but In this PSU I think i'nst the case because I need less than 30V as I said before...
I Hope you can understand me... and help me!  ;)
I am at your disposal.

[audioguru]

Hi Bugmenot,
Here is a parts list that I made a few years ago using bigger resistors. It uses a BD139 for Q2. It uses high voltage opamps but you can use TL081 opamps from the original project and the voltage reduction circuit used by Ivan.

[bugmenot]

For the original PSU I build can I make the Ivan proposal's (2nd 2N3055, bigger capacitor and 27 V for the opamps) and increase the resistor W's? I don't want to make another PCB for this PSU. And how can I effectively know the real PSU output or the Transformer output? How can I make this test? With a car light bulb,  a shower resistence, resistors or other method? Any Tips?
Thank you.

[audioguru]

Use Ivan's proposals if you want.
The transformer has a listed voltage and has a max allowed current. Multiply them to calculate its max allowed power.
The peak voltage of the transformer is multiplied by the max current from the project to calculate the actual power from the transformer. The original project does not have its max current calibrated so it is much too high and is well above 3A.

Don't test with a light bulb because when cool its current is 10 times or more higher than when it is incandescent. Use a heater as a load.

[Erivanst]

Here the pictures of my original project and the LCD module... After I post inside pictures of it ok?

Hi everyone!

Bugmenot, could you please post some information about the LCD meter that you cited?
I

[bugmenot]

Hi Erivan!
It's the meter proposed in the main page of the project, but in DIP version.
http://www.electronics-lab.com/projects/power/001/index.html (someone change the link)
Check the page of the author of the LCD meter:
http://www.elfly.pl/multimetr/multimetr_en_DIP.htm

[bugmenot]

http://www.electronics-lab.com/projects/test/022/index.html

[Erivanst]

Hi Erivan!
It's the meter proposed in the main page of the project, but in DIP version.
http://www.electronics-lab.com/projects/power/001/index.html (someone change the link)
Check the page of the author of the LCD meter:
http://www.elfly.pl/multimetr/multimetr_en_DIP.htm

Ok, Bugmenot. Thank you. This is one of the eschematics that I was looking. Good to know that you have build it. Didn

[PicMaster]

Just a quick question
Is there any reason why you could not use the quad vesrin of the TLE2141 instead of the three op-amps, Or would this have the effect the operation of U3 ?