Adafruit Feather 32u4 FONA

The Feather 32u4 FONA combines an ATmega32u4 microcontroller with a SIM800 GSM cellular module, giving you voice calls, SMS, GPRS data, and even FM radio in the Feather form factor. With built-in USB programming and LiPo battery charging, it's a complete cellular-connected development board.

The SIM800 cellular module supports quad-band GSM (850/900/1800/1900 MHz), making it compatible with 2G networks worldwide. A 500 mAh or larger LiPo battery is required to handle the high-current spikes during cellular transmission.

Key Features

• ATmega32u4 @ 8 MHz – 3.3V logic, 32KB flash, 2KB RAM
• Native USB – Built-in USB bootloader, serial debugging, and HID device support
• Quad-Band GSM (SIM800) – 850/900/1800/1900 MHz for global 2G coverage
• Voice Calls – With external 8Ω speaker and electret microphone
• SMS Messaging – Send and receive text messages
• GPRS Data – TCP/IP, HTTP, and other data protocols
• FM Radio Receiver – Built-in FM broadcast reception
• Bluetooth SPP – Serial port profile plus audio streaming
• AT Command Interface – With auto-baud detection
• 20 GPIO Pins – Including 10 analogue inputs and 7 PWM outputs
• Hardware Serial, I2C & SPI – Full peripheral support
• Built-in LiPo Charger – 500 mA charging via USB
• 3.3V Regulator – 500 mA peak current output

Specifications

• Dimensions – 61 × 23 × 7 mm (without headers)
• Weight – 8.2 g
• Mounting – 4 mounting holes

Required Accessories (Not Included)

• 2G Mini SIM Card – Required for cellular connectivity (T-Mobile or T-Mobile reseller networks recommended for US users)
• LiPo Battery – 500 mAh or larger required for stable cellular operation
• External Antenna – uFL connector for GSM antenna (sticker-type, SMA with adapter, etc.)
• Micro USB Cable – For programming and battery charging

Optional Accessories

• Electret Microphone & 8Ω Speaker – Required for voice calls

Also Available

• Feather 32u4 Bluefruit LE – With Bluetooth Low Energy
• Feather 32u4 Adalogger – With MicroSD card holder
• Feather 32u4 Basic Proto – With prototyping area
• Feather 32u4 RFM95 LoRa Radio (868/915 MHz)
• Feather 328P – ATmega328P variant

Ideal For

• Remote IoT deployments with cellular connectivity
• SMS-based alert and notification systems
• GPS tracking with GPRS data upload
• Voice-enabled embedded projects

Package Contents

• 1× Assembled and tested Feather 32u4 FONA
• 1× Header set