Don’t Spend Money On An Arduino – Build Your Own For Much Less

James Bruce 29-03-2013

build arduinoI love my Arduinos. At any point, I have quite a few projects on the go – prototyping is just so easy with them. But sometimes, I want to keep the project functional without buying another Arduino. Spending $30 each time for a fairly simple microcontroller than I only need some of the functionality for is just silly. It’s at that point that building an Arduino clone becomes a viable option.


The Truth: You Can’t Build a Full Arduino Clone For Cheaper

The Arduino itself consists of simple electronics, but it’s the package and the layout you’re really paying for. In this article I’ll outline how to replicate some of the functionality for a lot cheaper – in the case of “permifying” your Arduino projects – but it’s impossible to build a full DIY Arduino clone without having mass-purchasing power and production facilities.

The beauty of building your own is that you can exclude bits you don’t need to keep costs down, and avoid the Arduino package with all the unused headers and wasted space – if you really need the Arduino shape and headers for use with other shields, then building your own isn’t really going to save you any money.

In my case, I wanted to permanently display the LED cube I made How To Make a Pulsating Arduino LED Cube That Looks Like It Came From The Future If you’ve dabbled with some beginner Arduino projects, but are looking for something a little permanent and on a whole other level of awesome, then the humble 4 x 4 x 4 LED cube is... Read More somewhere, with an external power supply and not the added cost of using a full Arduino board; there was space left on the protoboard after all, so I’d rather put everything there. Here’s my finished DIY Arduino in breadboard stage, alongside the LED cube and an actual Arduino used for programming. The next step is to put all the bits on the protoboard, but that’s out of the scope of this article today.

build arduino

Anyway, on with the project. I’ve broken it down by section with individual component lists, but it’s easier to just buy a bundle (, £7.50).


Power Supply Regulator & Indicator LED

  • 100 uF capacitors (2) – careful of the silver line which faces the negative side
  • 7805 5V voltage regulator (1)
  • RED led and 560 Ohm resistor

build arduino from scratch

The purpose of this section is to take a 7-12v power supply (typically a 9V DC plug) and regulate it down to 5V needed by the microcontroller chip. The red and blue leads coming off left should be connected to whatever input power you’re using, but absolutely do not use more than 12v or you’ll fry things. Also, connect the top and bottom rails together at this point.

If you’re piggybacking off an existing Arduino to program the chip (described later on) you can also connect the power rails directly to the +5V and GND.

build arduino from scratch


Microcontroller & Timing Circuit

  • ATMega328P-PU – preloaded with Arduino bootloader.
  • 22pf Capacitors (2) (in the diagram they’re blue, but the component I bought were actually orange – no difference. There is no positive or negative to these).
  • 16 MHZ crystal.

For brevity, I haven’t shown the power regulator in the diagram below, but you should of course already have that bit finished.

build arduino from scratch

This part is the core of an Arduino – the microcontroller. The 16mHz crystal provides a constant timing signal which pushes each cycle of the circuit.

build arduino board


Also to make things easier on yourself, either purchase some of these Adafruit pinout labels ($2.95 for 10):

build arduino board

Or make your own. Here’s a PDF I made if you have sticky label sheets.

build arduino board


Reset Switch

Finally, we just need a reset switch – luckily this bit is pretty easy; but note that in some tutorials you will find a pull down resistor added. I believe this is needed for ATMega168 and not 368.

Don't Spend Money On An Arduino - Build Your Own For Much Less reset

Here’s the finished diagram.

Don't Spend Money On An Arduino - Build Your Own For Much Less everything

The Dx’s and Ax’s are then your regular Digital and Analog I/O pins. If you choose not to make life easier on yourself with a printout, please be very careful not to confuse anything says D13 or pin 13 on the Arduino, with pin 13 of the ATMega328. They are different – D13 is actually pin 19 on the chip. RX is also functionally D0, and TX is D1.

Programming The Chip 

Before you can test this out, you’re going to need some way of programming the ATMega chip – this is where the complication comes in. On an Arduino board, one of the most expensive parts is the USB interface.

Here’s your options:

1. Take The Chip Out Of Another Arduino.

This is the easiest route for quick testing; just use an existing Arduino board with your working sketch already on it, and pull out the chip from the Arduino. If your project is finalised and working, just swap them around. You can throw another unprogrammed chip into the Arduino to use again – there’s nothing special there.

The only downside here is that it’s very easy to damage the pins, so be VERY careful when removing them.

 2. Use A Passthrough Cable From An Existing Arduino.

Before attempting this, you must also remove the existing chip from your Arduino; it will interfere with the process. Essentially we’re just going to use the USB interface of the Arduino. Connect power and GND to the standard Arduino pins; Reset; and the most important part – RX to RX (D0), and TX to TX (D1) – these are the send and receive serial pins then you should be able to use the USB port on your original Arduino.

3. Buy An FTDI USB To Serial Interface Cable.

This is basically a replacement of the interface included in all Arduino’s, but pretty pricey at around $15 – and is the main reason why you can’t cheaply build an exact replica of an Arduino. If you plan on doing this a lot though, getting one of these that you can just keep on the end of a USB cable is probably the easiest route to go.

For instruction on adding this, follow the diagram provided by Oomlout [Broken URL Removed], only taking note of the USB programming interface shaded area. Use the 6 pin header to connect the actual interface.

build arduino

Note that all these methods assume you have an Arduino bootloader already burnt onto the chip; if you buy as a component bundle, for example, they will be provided ready to simply swap out. If you buy the chips on their own or not specifically for an Arduino purpose, you’ll need to use something else to burn the bootloader first. There’s a good tutorial here on piggybacking an existing Arduino and an application called OptiLoader  for that purpose. The difference is about $2.

So, before buying another Arduino for the next project, ask yourself: do you need the USB connection, and do you need to connect Arduino shields? If the answer to both of those is yes, then go ahead and buy another Arduino – it won’t work out any cheaper by building your own. Otherwise, just build one yourself! And don’t forget to check out all the rest of our Arduino tutorials and articles.

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  1. fatima
    July 16, 2017 at 7:06 pm

    It's very interesting and very motivating and inspiring too....I just decide to made my own aurdino

  2. Dagrith
    December 17, 2016 at 5:18 am

    on the diagram by Oomlout I don't understand what c3 c4 c5 and c6 are

    • James Bruce
      December 17, 2016 at 9:08 am

      Capacitor. The value is written close by.

  3. Colin
    December 11, 2016 at 11:35 pm

    Will two 20 pf capacitors work for this? I can buy the 16 mhz crystal from adafruit but they come with 20 pf capacitors so it would be nice if it worked with them :)

    July 1, 2016 at 7:54 am

    I made this on breadboard but digital read functions are not working.
    Can you please tell the reason

  5. Anonymous
    October 12, 2015 at 10:04 pm

    I think the main advantage to have a develop board, arduino one in this case, it is to have everything on PCB, surely we can build our own board, with PIC's or avr uC's, but achieve a semi pro pcb (or pro, like arduino) it will take time, time that could to spend properly in an application

  6. izik
    February 24, 2015 at 12:21 pm

    now u can by arduino for $4 at aliexpres.

    • James Bruce
      February 25, 2015 at 7:36 am

      You can buy an Arduino-compatible clone, yes. The reason for making your own would largely be for embedding it or some kind of customization - buy clones is far easier and cheaper, I agree.

  7. Yonsebastian
    September 21, 2013 at 3:07 am

    Great, i'd love have the time to do things like this.

  8. satviksr
    May 18, 2013 at 9:33 am

    How do u make those nice animated pic of the breadboard?

  9. Craig Stevenson
    April 2, 2013 at 2:47 am

    I've been meaning to get busy and build an LED Cube but I guess I should build my own Arduino clone to run it with. That should keep me off the streets for a while. Thanks for a great article.

  10. Chris Marcoe
    March 30, 2013 at 1:51 am

    So, would it be possible to build a Pi clone? Cause I have one of those and love it. Wouldn't mind have 2 or 3 more.

  11. Michael Heffner
    March 29, 2013 at 6:51 pm

    I really need to spend more time using these.