Before you order, please read the whole description, the price will change based on the selected option:

• PCB - $1
• PCB + components + $10.5
• PCB + assembled components + un-soldered pin terminals + 15$

In case of assembly, you pay for my time assembling and testing. If you like to solder or learn to solder, then KIT is for you. If you want to use it out of the box, then the fully assembled unit is for you.

Each board is hand-assembled, no pick and place, this is why it is not so cheap.

What is it?

Bare PCB/kit/fully assembled board (check options on the right) for Atmega328PB(P/PA compatibility via solder jumpers) with Arduino nano compatible pinout expect two pins. For USB to serial conversion, CP2102 chip is used. This chip is required if you want to use upload over USB (with bootloader) if ICSP is used then this chip does not have to be soldered.

This board has two more pins compared to classic Arduino Nano (PE0 and PE1). In the Arduino environment, these pins are D23 and D24. But these are not labelled on PCB - I wrongly marked them as pin 13 and 14, so they are repainted to avoid mistakes. Pins A6 and A7 are more than just analogue inputs (PE2 and PE3).

Enhancement and Additional Features in ATmega328PB

Compared to existing ATmega328 variants, the following enhancements or additional features are available in ATmega328PB: • PTC - Peripheral Touch Controller. • CFD - Clock Failure Detection mechanism. • OCM1C2 - Output Compare Modulator. • USART start frame detection is available in all sleep modes • Analog Comparator output is available on a pin. This pin is multiplexed with PE0. • Unique device ID to identify the device • Additional USART • Additional SPI • Additional TWI • Additional Timer/Counters

For more information about the difference between 328 chips, check this PDF on the Microchip website.

Why did you make it?

I need AVR microcontroller for a project with easy to solder package and two I2C. I found an upgraded version of ATmega328, so I challenged my self to create Arduino Nano compatible boards with this chip. While I was playing with this, I also designed this set of boards for other upgraded chips:

• Atmega328P/PA/PB board compatible with Arduino nano
• Atmega328P/PA/PB board compatible with Arduino Uno
• Atmega324P/PA board compatible with Arduino nano (PB version not produced yet, only designed, check GitHub)
• Atmega324P/PA board compatible with Arduino mega (PB version not produced yet, only designed, check GitHub)
• Atmega2560 board compatible with Arduino mega with all pins routed to pin-headers

What makes it special?

• support for PB version of ATmega328 (4 more IO)
• better usb to serial chip (CP2102) then on chines clones
• still open source

Arduino support

To use PB version of ATmega328 chip with Arduino IDE you need to install MiniCore from MCUdude: https://github.com/MCUdude/MiniCore.

Selecting PB/nonPB version of installed chip

On the board, there are three jumpers: - two are 3-pins marked as PA|PB used to select installed MCU - the third one is 2-pin jumper used to connect DTR pin of cp2102 to reset line of ATmega MCU over 100nF capacitors used for the auto-reset feature.

Order options:

• PCB - bare PCB
• KIT - PCB + parts, nothing is soldered, chip is not pre-burned with any sort of bootloader. Download assemly plan here.
• Assembled - fully assembled product, tested, chip is preprogramed with optiboot bootloader from Minicore repository.

Bare PCB.

kit option

Assembled unit

Why not RX/TX leds?

There is the place for the RX/TX LEDs on PCB (unpopulated R8, R9, D3, D4), but I made an error in design and routed them to the ground. They should connect to 5V rail. I was about to run new PCBs when I realize this will only work with a more expensive CP2102N chip, as this one uses separate pins for the LEDs. Legacy CP2102 chip did not have this function (LEDs in case of CP2102 are tied directly to the RX/TX lines). And as I want to use the CP2102 chip, I decide that these LEDs are not so important, and rolling new PCB is just a waste of money, and it's not ecological. But this can be hacked. Check the GitHub page for more information.

Opensource

All design files are on GitHub in my personal HW repository.

Problems, suggestions

I created this for my needs, and as I have spare boards I sell them. All files to this project are available to check before the order, on GitHub. All bugs are mentioned here. In case of any problems contact me, I do my best to resolve any issue or talk about any suggestions. If you are skilled in GitHub ecosystem and have an account there feel free to fill an issue there, do not forget to mention that you are talking about nanoPB.