How to Make a Voltage and Current control, Short Circuit Protected Adjustable Power Supply 30V/10A

Hey Guyz, This time I'm making a variable bench power supply. This is the most useful equipment for a hobbyist and DIY maker cause while making or testing circuits, it needs different values of voltage and current. That's why every DIY maker must have their own bench power supply. Now I'm going to show you how to build an awesome variable bench power supply. So take your tools and let's get started :)

If you like this project then please do vote for me :)

I'm using here LTC3780 DC adjustable buck and boost converter. which is an amazing module. It can deliver DC (1-30V) and up to 10A current depends on your input power source, in my case I'm using DC 12V 3A input power source. I easily get continuously adjustable output voltage (1-30V) and current (0-6A), which is pretty enough for circuit testing and other things. I'm also using 7805 voltage regulator IC for 5V constant voltage and current.

This Power Supply Has Following Features:

Input Voltage 12V DC.

Input current 3A.

Output Voltage (1-30V) Continuously Adjustable.

Output Current (300mA-6A) Continuously Adjustable.

Output ripple 50mV.

Constant voltage and constant current.

Additional 5V Constant Output.

Short Circuit Projection.

We need these following parts to build the power supply. I bought some from online and some from the local store.

Parts List:

LTC3780 DC Adjustable Converter

Digital Voltmeter Ammeter Display

500k & 200k Linear Potentiometer

12V DC Fan

7805 IC For 5V

12V 3A Adapter

100uF & 10uF Capacitor

1N4001/1N4007 Rectifier Diode

Banana Socket 4ps

Knob 2ps

DC Switch

2.1mm DC Jack Connect

Wires

HeatSink

Wooden Blocks

PCB Board

4mm Acrylic Sheet

Tools List:

Glue Gun

SuperGlue

Sandpaper

Mini hand saw

Soldering Iron

Masking Tape

Drill Machine

Rotary Tool

I'm using here acrylic sheet to make the enclosure of my power supply. This is an amazing material cause it is easy to cut, bend and sand. It's also so affordable. You can use the acrylic sheet to make your own power supply. So let's get started.

First, take a measurement of acrylic sheet.

Cut the acrylic sheets according to the marking.

Place the voltmeter display and mark it.

Next cut the marked section with a rotary tool and metal file.

Again mark the areas for air passing

Cut the marked area using a mini hacksaw.

Take the measurements of dc socket, dc switch and dc fan, then mark it.

Drill the holes and smooth the edges with a metal file.

First, remove the paper cover from the acrylic sheets. Then sand the acrylic sheets until getting a smooth flat surface.

We'll start off by applying super glue on the edges of upper and lower panels. Next, attach the side panels to each panel.

I decided to paint the upper and lower encloser of my power supply. I choose matt black color for my power supply.

We need some extra pieces for mounting screw. Now take four same size pieces and attach these pieces using super glue.

First, apply a great amount of superglue on the edges of the front panel. Next, quickly position it to the lower encloser, then hold it for a couple of minutes. Use this same method to attach the back panel.

In this step, we'll mount every component. First, we'll start off by mounting dc switch. Then we'll use the screw to mount the dc fan. Then we'll mount other components respectively.

It's necessary to reduce the temperature of the power supply. So we need a heatsink and a cooling fan. Though LTC3780 dc converter has an inbuilt heatsink and this converter doesn't heat up. You can skip the additional heatsink. I'm here additional heatsink for better efficiency.

First drill holes on the wooden block

Use the screw to attach the heatsink to the wooden block.

Now apply hot glue on the wooden block.

Attach the wooden block to the enclosure

In this step, we're going to replace the inbuilt potentiometer of LTC3780 with the linear potentiometer.

First, remove the inbuilt 500k and 200k trimmer potentiometer using soldering iron.

Now solder wires to solder joint of the trimmer potentiometer.

Solder those wires to new 500k and 200k linear potentiometer.

Note: When removing the trimmer potentiometer make sure that you do not heat the board too much. it could damage the dc converter.

I'm using here 7805 IC for addition 5v constant output. First, solder the components then add a heat sink to reduce the heat.

This is the complete circuit diagram of this power supply. You've to connect every component according to this circuit diagram.

In this step, we'll solder every component according to the circuit diagram. After soldering every component, I tied all the wires with zip ties.

Now attach the upper enclosure with screws. Finally, we're done now. Plug the dc jack and the power supply ready to provide (0-30)V and Up to 6A Output Current.

Thanks for watching this instructable. If you like this project then please vote for me. I really need your vote and I know that you will do it.