A variable power supply is an essential tool for any electronics enthusiast or maker. It allows you to easily adjust the voltage and current output to power and test different electronic circuits. In this tutorial, we will show you how to build your own variable power supply using the UC723 IC, TIP41 transistor, and 2N3055 transistor. This power supply can output a voltage range of 1.2-30V and a current range of 0-10A.

After designing the circuit, it is important to transform it into a PCB design to produce a physical version of the circuit. There are many PCB suppliers available, but for this project we have chosen JLCPCB as the best and cheapest PCB provider. To order the PCB from JLCPCB, you will need to follow a few simple steps. First, visit the JLCPCB website and upload the Gerber file for your circuit design. You can then choose the PCB specifications, such as the size, thickness, and number of layers. Next, choose the quantity and any additional options, such as silk screen printing or solder mask. Finally, proceed to checkout and pay for your order. The PCB will be manufactured and shipped to you within a few days. Once you receive the PCB, you can start soldering the components onto it to complete your power supply. As shown in the pictures, the PCB is well-manufactured and includes all the labels and logos to guide you during the soldering process. You can also download the Gerber file for this circuit from the link provided in case you want to order the same circuit design.

The UC723 IC is a pulse width modulator (PWM) control chip that is used to control the output voltage and current of the power supply. The TIP41 transistor is used to amplify the current output and drive the load, while the 2N3055 transistor is used to provide additional current amplification. The 7805 voltage regulator is used to provide a stable 5V supply for the UC723 IC.

To adjust the output voltage, we will use a potentiometer connected to the control input of the UC723 IC. The output voltage of the power supply is then determined by the duty cycle of the PWM signal generated by the UC723.

To adjust the output current, we will use a second potentiometer connected to the base of the TIP41 transistor. This adjusts the base current of the transistor, which in turn adjusts the collector current and the output current of the power supply.

First, you will need to assemble the circuit on the PCB board. Begin by soldering in the UC723 IC Base.

Next, you will need to solder in the rest of the components according to your circuit design. This includes the resistors, capacitors, potentiometers, and transistors. Be sure to double-check your connections and make sure that everything is properly soldered in place

Once you have built the power supply, you can test it by connecting a load to the output terminals and adjusting the voltage and current potentiometers. Make sure to start at low voltages and gradually increase the voltage and current to avoid damaging the circuit or the load.

• Use the potentiometer to adjust the output voltage to the desired level.
• Use the panel meter to monitor the output voltage and current.

That's it! With a little bit of soldering and some basic electronics skills, you should be able to build your own variable power supply using the UC723 voltage regulator..

Note: Make sure to use caution when handling high voltage and current, as it can be dangerous if not handled properly. Always follow proper safety guidelines and use protective equipment when working with electronics.

• Download Gerber file from HERE.

New users will also get some coupons while registering at JLCPCB via this blue link.

Thank you for reading this guide, hopefully, this guide provides full steps to help you to create your own "DIY Variable Power Supply". If you have any questions please post them in the comment section below.