0-30V Laboratory Power Supply


This project is based on the 0-30 VDC Stabilized Power Supply with Current Control 0.002-3 A and a new PCB layout is introduced here. It’s a stabilized power supply with variable output voltage in the range 0-30Vdc (33Vdc peak) – and variable current 3A and is ideal for your laboratory power supply.


Schematic and PCB are designed in Eagle software and the source files are available on the links at the bottom of the page. The PCB design has connectors for 2N3055 transistor, input and output voltage. Also on-board potentiometers are added.









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Actually that PS is NOT that bad, it is just old design and fully good for home lab.

Sorry, typing too fast :(.

Sooraj S A

where to place 2n3055 its outside the layout

Sooraj S a

Will this circuit work as i am seeing many negative comments for the loaded pcb design and components…actualy i bought the components and is in dilemma to proceed or not…

Francisco Ferreira

Sir, may you awnser my question ? I have a doubt. I assembly the other one, the one you based this project. And as long if I got original components, it worked fine for me. Until one day I let the power supply conected over night, with no load, so the peak voltage on the filter capacitor increased and burn it. And this problem repeats once more. Your power supply may suffer the same problem ? Also din’t find the tl081p TL081 is ok ?


The 2n2219 is not available in my area. What else I can use?


You can replace it with a 2n2222, no additional changes necessary

Ben Houria

hello everybody
please, this PS is correct or no?


This is a good instruction. I am just a newbie, and i want to build this project. I just want to use it as my own (not hard use). So will it work perfectly? I just use it for my lab


Hello . I need set current from 0 to 5 Amp . How i can change circuit to do this ?

Yeinier Ferrás

Hello, Thanks by your work. May I use other type of AOs like LM358?, I have some of them and I like to use them in a power source like this.

amir victor

hi sir. i have 2 Q
1(Important)-how can i upgrade it to 0-30V 0-5A ?
i used a 5A Transforme but the current is limited on 3A and i can not use more than 3A ?
2(Non-Important)- how can i add FINE Volume side of this 2 volumes?


im still waiting for my answers 🙁


5 years ago… and nobody answered. I have one to the second question: use two potentiometers in series instead of one with two other resistances. It is necessary, the two potmeters resistance have to be close as possible to the original value. 27k~24k+2.2k or something like this. The smaller one will be the fine, the bigger will be the corsare.

Dominic Murray

hi can i make a negative supply out of this..

Alaa M Nasser

what are the correct values for this project and does it work properly

Naeem Ahmed

I use 18 volt 2.5 ampere transformer use circuit working good if i use 32 volt 2.5 ampere transformer u3 overheat and circuit not working plz solve my problem

Deivi de Jesus Luis Dominguez

the list of components is not listed

Toni Uusimäki

Hi and thanks for this project.
Yet when I run the pcb-code, the eagle.exe crashes.
First I thought it was the extra transistor Q4 from the board, since
it complaint about airwires.
From eagle manual 8.8 I defined an attribute _external_ and
was able to remove the Q4 from the board editor. But this did not
stop the crashing.
Any ideas?



Sir could you please send me the components value


sir can I use UA 741 instead of TLO 81 because TLO 81 is not available