Many electronics circuits and projects for learning in simple ways.

0-50V 2A power supply circuit,voltage adjustable using UA723-2N3055

This is a 0-50V 2A power supply Circuit. It can be adjustable voltage output.  by IC LM723 + Transistor 2N3055 & BD140 & A671 is nice Power supply.

For all electronic user. You can Current control by VR 5K, LED5 For display OVERLOAD.
To use transformer 3A, Transistor to Hold Heatsink. To adjust the output voltage< VR1 – 5K (VOLT CONTROL)

OUTPUT : 0V to 50V , 2A

Today I would like to introduce you to DC Voltage adjustable regulator voltage between 0V to 50V and current up to 2A. Which are suitable for various electronic circuit, when viewing circuits in the figure, many people will think that, in this circuits outdated, but I think, it is also highly effective are.

The output delivers DC stable voltage from 0V to 50V, by adjusting potentiometer- VR2.

-The VR1- 5K be fined current output load 0 to 2 Amp.
– When the short-circuit current limit or severe, it is a good system.
– Low noise, due to the use IC uA723 dc voltage regulator IC which is high quality, widely used for many years.

This circuit uses transistors A823, 2N3223, 2N3055 is boost up current to 2 amp.
When a short-circuit. LED1- Overload status light will not have current to output and The three transistor TR4,TR5,TR6 works. Then when we check the circuits we tested, it usually works well, we press S1 to circuits to work normally.

In addition, this circuit. It is not difficult to create a PCB layout and equipment are. I hope this is helpful to you.
Almost forgot, you should the use transformer to optimize 3Amp size of the circuit.

Note: But if you are not satisfied. We also offer this power supply circuits. Supply voltage 70V maximum ever.

0-70 Volt 2 Amp DC variable power supply


DC voltage adjustable power supply 0-50V up to 2A by ua723-2N3055

DC voltage adjustable power supply 0-50V up to 2A by ua723-2N3055

PCB of DC voltage adjustable power supply 0-50V up to 2A by ua723-2N3055
PCB of DC voltage adjustable power supply 0-50V up to 2A by ua723-2N3055

We recommend

This project is very ancient so you should build below:

The circuit diagram of 0-50V 3A Variable DC power supply

This Post Has 15 Comments

  1. Well, I built the circuit supply voltage DC 0-50V adjustable up to 2 A per-2N3055 UA723 but does not work. I don’t know why. There is a confution with transistors specs, A823, A671 or 2N3223,BD140????? Anyway, doesn’t works!

  2. hello
    what are the values for the diode d4 and the zener diode zd3

  3. see the ics spacification search on google then u know thw perfect value

  4. gan minta layot pcb o-50v gan,,,,,,,thanks

  5. The answer of Gajendra is not to be taken seriously to say it politely. He could also go to Google to check his use of the English language. Why doesn’t he give a clear answer? Everyone knows the value in current of the transformer is to be 25 or 50% higher than the final deliver current. But what are the specs in voltage of the transformer and why doesn’t he use a bridge rectifier?

    I heard more than one comment that the project doesn’t always work. Why? 50V is close to the limits most LM723 can swallow. You better use a L146etc if you can still find one.



  6. The right part of this circuit is working, you must connect tr3-base with tr3-emitter only then you have exactly the same as “0-70 Volt 2 Amp DC variable power supply”. In my case the R100 below TR1 is very hot @32V2,3A and I can’t obtain more Amp even if I connect second TR1 (my transformer have enough power).
    Notice that I build this on “Solderless Prototype Breadboard”.
    When I build the whole circuit it burned the wires 🙂
    In short: don’t build this 🙂

  7. it does work but the circuit has error in it. the lm723`s pins 10 and 11 must be reversed otherwise you are powering the ic through the output and expecting DC through the input. otherwise it should work brilliantly. i just dont get one thing. is the current control linear or is it switching. i mean when you overload it does it just knee to zero volts until reseted or does it just stop at 2A no matter the load?

  8. In regards to Cedric’s Comment;

    The Reason he doesnt use full bridge rectification is the same reason i didnt use an apostrophe in the body of my message, it isnt required. After you send a signal through the transformer you get half rectification on the other side, the two diodes on the output of the transformer finish off the rectification leaving it fully rectified…i believe is the theory behind it

  9. hello, i want to develop -48V,3A power supply can anyone provide me the circuit diagram please this us my minor project.

  10. We need to consider the key elements required in a
    Best Practice supply chain design. The focus of the work is on the content, not the navigation, layout, etc because Joomla allows non-techie’s to easily update and
    add content means you can say that Joomla is very user friendly
    CMS. This helps in optimizing the redundancy problem and excessive hard-copy handling.

  11. Hello what should the output voltage of the transformer be? 35V? i have a 35-0-35V transformer should i pararell them?Or does someone have a dual trace PS to use this transformer?Thank you

  12. For the rectifier issues.

    For the fullwave rectifier as shower
    Volts DC = 0.71 x Volts AC
    Amps DC = Amps AC

    If a bridge rectifier was used
    Volts DC = 1.41 x Volts AC
    Amps DC = 0.62 x Amps AC

    Remember to slightly oversize the current rating for your transformer, as they can hum under high load and voltage can start to drop near there maximum capacity.

    I haven’t tried to build this circuit or examined it in detail, but WHERE IS YOUR FUSE? I see AC through the transformer straight into the circuit with no protection at all.

    He has connected to Pin8 on the LM723 which is a NC (no connection) so he has the IC layout wrong I am assuming he wanted to join 5 and 6. 10 and 12 should not be joined, it should be 11 and 12 with Pin 10 as Vout.

    I am not even going to bother looking at his current limiting in detail, or the orientation of Transistors as people have mentioned. I would just plainly avoid this circuit.

  13. Why there is no value for the diode D4 dan Zener D3 and the output voltage of the transformer for 0-50V/2A power supply circuit

  14. can i use the current sensor of the lm723 in this circuit

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Close Menu