SparkFun Qwiic Dynamic NFC/RFID Tag

Make your next project interact directly with smartphones and RFID readers using the SparkFun Qwiic Dynamic NFC/RFID Tag. Built around the Near-Field Communication (NFC)/Radio-Frequency Identification (RFID) ST25DV64KC IC from STMicroelectronics^©, this tag provides 64-kbit (8-kbytes) of EEPROM memory that can be accessed via both a wired I²C connection and wireless RF. What makes this board incredibly useful is its ability to be read from and written to via NFC, even when your main circuit is completely powered down or disconnected!

Connection Options and Built-In Range

This board offers two distinct interfaces for powering and communicating with the ST25DV64KC. A pair of onboard Qwiic connectors routes the SDA/SCL lines alongside 3.3V and Ground, so you can start communicating over I²C instantly without soldering. For more permanent installations or custom breadboarding, a standard 0.1-inch-spaced PTH header breaks out the power pins, I²C interface, energy-harvesting pin (VEH), and general-purpose output (GPO).

To establish a reliable wireless connection, the board features a built-in PCB antenna designed to boost the RF read range. In real-world testing, this provides a comfortable scanning distance of a few centimeters when used with a standard smartphone NFC reader app.

Smart Features for Advanced Projects

Beyond basic data storage, this tag is packed with features for advanced RF applications and conforms to the ISO/IEC 15693 and NFC Forum Type 5 standards, ensuring excellent compatibility with modern devices.

• Data Letterbox: Features a fast transfer mode that uses a 256-byte buffer to quickly pass data between an I²C-connected microcontroller and an RF device.
• Energy Harvesting: Includes a dedicated pin capable of outputting microwatts of power when the board is placed in an RF field of sufficient strength.
• Configurable Interrupts: A general-purpose output (GPO) pin can trigger external interrupts for events like RF field changes, I²C writes, or RF activity.
• Custom Security: Protect your data by dividing the user memory into up to four configurable areas, each of which can be secured with distinct 64-bit passwords for both I²C and RF access.

Ready for Your Smartphone

To make integration as smooth as possible, our comprehensive Arduino Library includes everything you need to modify memory regions, implement password controls, and format your data. We have also included built-in methods for reading and writing NDEF (NFC Forum Data Exchange Format) records. This means you can easily program the tag to share URLs, WiFi credentials, or plain text that a smartphone can natively interpret, and it has been fully tested with apps such as ST's "NFC Tap" (available on the Apple App Store and Google Play) and wakdev's "NFC Tools."

Whether you are building an interactive art installation, a smart inventory system, or simply want to share WiFi credentials with guests with a tap on their phone, this tag gives you the memory and flexibility to make it happen!

• Schematic
• Eagle Files
• Board Dimensions
• Hookup Guide
• Datasheet (ST25DV64KC)
• "NFC Tap" App
  • iOS
  • Google Play
• wakdev's NFC Tools
• Qwiic Information Page
• Arduino Library
• Library Documentation
• GitHub Hardware Repo