Minimalist Arduino for $3

in Arduino, AVR, DIY by the machinegeek | 10 comments

What’s the fewest components you need to have a functional Arduino? Wolf Paulus gets it down to just an Atmega168 chip, power connector and LED for good measure. He describes, “This is probably the most minimal ATmega168-20PU based Arduino you can come up with. The ATmega168 (available for about $3) was the default Arduino chip for quite some time, before being replaced by the ATmega328, doubling the available memory. The chip is powered with +5V on Pin-7 and grounded via Pin-8; the LED is between Pins 19 and 22.” He suggests a minimalist Arduino could be useful when integrated with a Raspberry Pi to enhance the the R-Pi’s analog input capabilities.

This variation is minimal in both hardware and firmware as the chip functions without a bootloader. This requires the addition of a new hardware definition in your Arduino IDE, and programming via an Atmel or similar programmer instead of over serial.

You can find all the details and code on Wolf Paulus’ website.

This entry was posted in Arduino, AVR, DIY and tagged .


  1. Bertho says:

    The minimalist version needs one more component: a decoupling capacitor.

    It will set you back at least 2 cents, making it an investment of (in)significant proportion, but will keep you from despair when things go awry.


  2. McMonster says:

    No decoupling caps, not all power pins connected, no resistor for LED, not even a bootloader flashed. The worst idea I’ve seen recently, I hope no beginner will EVER see this, because it is entirely bad and will work unreliably and randomly. Suggesting this “project” as analog interface for Raspberry Pi is even more awful with this kind of setup (power supply and filtering).

    Please don’t promote bad projects here.

  3. Xavis says:

    I really don’t understand the trend of baptising anything microcontroller related as an Arduino. Why belittle the concept of a microcontroller to petty branding…

    • Oliver says:

      If anything, you could concider ‘arduino’ the bootloader. Without it, this isn’t even an arduino in the most bare sense anymore, it’s just an atmega … just that.

      • Faizan says:

        OR we could call the entire IDE and its set of libraries the Arduino. It is afterall the main thing responsible for simplifying C code, making it more accessible.

  4. Peter says:

    You HAVE TO connect resistor beetwen Atmega8 port and LED. Whitout it supply voltage is pulsing about 2V !!. Also You have to connect 100uF and 2.2uF near uC beetwen VCC and GND !

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