With this Feather we’re getting a little nostalgic for the ATmega328P – the classic ‘Arduino’ chip – with this Adafruit Feather 328P running a 3.3V and 8 MHz. Feather is the new development board from Adafruit, and like it’s namesake it is thin, light, and lets you fly! We designed Feather to be a new standard for portable microcontroller cores. We have other boards in the Feather family, check’em out here.

At the Feather 328P’s heart is an ATmega328P clocked at 8 MHz and at 3.3V logic, a chip setup we’ve had tons of experience with as it’s the same as the Pro Mini and similar to the Adafruit Metro 328. This chip has 32K of flash and 2K of RAM, and we paired it with a SiLabs CP2104 to give it USB-to-Serial program & debug capability built in. Works great when you want to keep your classic Arduino code compatibility, but want to use one of our dozens of FeatherWings

To make it easy to use for portable projects, we added a connector for any of our 3.7V Lithium polymer batteries and built in battery charging. You don’t need a battery, it will run just fine straight from the micro USB connector. But, if you do have a battery, you can take it on the go, then plug in the USB to recharge. The Feather will automatically switch over to USB power when its available. We also tied the battery thru a divider to an analog pin, so you can measure and monitor the battery voltage to detect when you need a recharge.

Here’s some handy specs!

• Measures 2.0″ x 0.9″ x 0.28″ (51mm x 23mm x 8mm) without headers soldered in
• Light as a (large?) feather – 4.8 grams
• ATmega328p @ 8MHz with 3.3V logic/power
• 3.3V regulator with 500mA peak current output
• USB serial converter (CP2104) for USB bootloading and serial port debugging
• You also get tons of pins – 19 GPIO pins + 2 analog-in-only pins
• Hardware I2C, hardware SPI support. For UART devices, should use SoftwareSerial
• 6 x PWM pins
• 8 x analog inputs (two are shared with I2C)
• Built in 100mA lipoly charger with charging status indicator LED
• Pin #13 red LED for general purpose blinking
• Two LEDs for serial data RX & TX
• Power/enable pin
• 4 mounting holes
• Reset button

The Feather 328P has some extra space left over, so we give you a tiny little prototyping area. If you just need to attach a button or sensor, you may be able to skip out on a breadboard and wire it directly on there.

Comes fully assembled and tested, with a USB bootloader that lets you quickly use it with the Arduino IDE. We also toss in some header so you can solder it in and plug into a solderless breadboard. Lipoly battery and USB cable not included (but we do have lots of options in the shop if you’d like!)

Technical Details

Product Dimensions: 50.0mm x 22.8mm x 7.2mm / 2.0″ x 0.9″ x 0.3″

Product Weight: 4.6g / 0.2oz

The Adafruit Feather 328P is a compact and powerful development board featuring the classic ATmega328P microcontroller running at 3.3V and 8 MHz. Designed as part of Adafruit’s Feather family, this board provides a lightweight, portable solution perfect for a variety of electronics projects requiring Arduino code compatibility.

Key Features:

• ATmega328P microcontroller @ 8 MHz, 3.3V logic
• 32K flash memory and 2K RAM
• CP2104 USB-to-Serial converter for programming and debugging
• Built-in battery charging for 3.7V Lithium Polymer batteries via JST connector
• Automatic switch between USB power and battery power
• 19 GPIO pins plus 2 analog-only pins
• Hardware I2C and SPI support; SoftwareSerial for UART
• 6 PWM pins and 8 analog inputs (two shared with I2C)
• 100mA LiPo charger with status LED
• On-board red LED on pin #13, RX and TX LEDs
• Power/enable pin, reset button, and four mounting holes
• Small prototyping area for custom circuitry
• Dimensions: 2.0″ x 0.9″ x 0.3″ (51mm x 23mm x 8mm)
• Weight: 4.6 grams

The Feather 328P comes fully assembled, tested, and ready with a USB bootloader for easy use with the Arduino IDE. Headers are included for soldering to breadboards. Note: LiPo battery and USB cable are sold separately.