Adafruit
Adafruit ST25DV16K I2C RFID EEPROM Breakout - STEMMA QT / Qwiic
The Adafruit ST25DV16K is a unique I2C-programmable RFID EEPROM breakout that works with mobile phones as an ISO/IEC 15693 (13.56 MHz) NFC tag, but can be dy...
The Adafruit ST25DV16K is a unique I2C-programmable RFID EEPROM breakout that works with mobile phones as an ISO/IEC 15693 (13.56 MHz) NFC tag, but can be dynamically rewritten over I2C by a microcontroller. This makes it ideal for projects where you need to change tag content on the fly — for example, cycling through different URLs that a phone detects in sequence.
The breakout includes the ST25DV16K chip, support circuitry, and a PCB trace antenna. STEMMA QT / Qwiic connectors allow solderless I2C connections, and standard 0.1" headers are included for breadboard use.
Key Features
- ST25DV16K Chip – 16 Kbit I2C EEPROM with ISO/IEC 15693 RFID interface
- I2C Programmable – Dynamically rewrite NFC tag content from a microcontroller
- Phone Compatible – Readable by Apple and Android devices as an NFC tag
- PCB Trace Antenna – Built-in antenna, no external antenna needed
- STEMMA QT / Qwiic – Solderless I2C connectors on both sides
- Bidirectional Data Transfer – Can be used as an I2C-to-RFID bridge for wireless data exchange with mobile devices
Ideal For
- Dynamic NFC tags that change content programmatically
- Interactive displays and exhibits
- Wireless data transfer between microcontrollers and phones
- IoT projects requiring phone-readable tags
Package Contents
- 1× ST25DV16K breakout board with PCB antenna
- 1× Header strip
Resources
Jargon buster
Plain-language definitions for the technical terms used above.
- ATmega328P
- An 8-bit microcontroller chip used on many Arduino Uno-compatible boards. Knowing the controller uses an ATmega328P helps you understand its memory, speed, pin compatibility, and the Arduino sketches it can run.
- breakout
- A breakout is a small circuit board that makes a tiny or hard-to-solder component easier to connect to with standard pins. It matters because this OLED module can be wired into a microcontroller project without needing to solder directly to the display’s fine contacts.
- CircuitPython
- A beginner-friendly version of Python designed to run directly on microcontroller boards. If a product supports CircuitPython, you can often program it by copying code files onto the board rather than setting up a more complex toolchain.
- EEPROM
- A type of non-volatile memory that keeps stored data even when power is turned off. In a sensor module, it can be used to store settings or calibration data so they do not need to be re-entered every time.
- Headers
- Rows of metal pins used to plug a module into a breadboard or connect it with jumper wires. Pre-soldered headers make the module easier to use straight away without needing to solder the pins yourself.
- I2C
- I2C is a two-wire communication bus used by many sensors and small modules. It matters because several I2C devices can share the same two wires, but each device needs a compatible address and your controller must support I2C.
- IoT
- Short for Internet of Things, meaning physical devices that connect to networks or the internet to send data or be controlled remotely. It matters if you want projects such as connected sensors, remote controls or classroom data-logging activities.
- microcontroller
- A microcontroller is a small computer on a chip that runs your program and controls connected inputs and outputs. For this product, it is the part that reads buttons and sensors, drives the display and speaker, and communicates over Bluetooth.
- PCB
- A printed circuit board is a rigid board with copper tracks that connect electronic parts without loose wires. For this kit, the PCBs also form the airplane shape, so they are both the circuit base and part of the finished model.
- PCB antenna
- A PCB antenna is an antenna pattern built directly into the circuit board rather than a separate metal antenna. It matters because placement, nearby metal and enclosure design can affect wireless range.
- Qwiic
- Qwiic is a plug-in connector system for I2C devices that uses small 4-pin cables, so you can connect compatible sensors without soldering. It matters because your controller or adapter also needs Qwiic, or you will need a cable or breakout to wire it up.
- RAM
- RAM is temporary memory used while a device is running, and its contents are lost when power is removed. A “Run in RAM” mode is useful for testing settings without permanently programming the module, but it may not support every feature.
- STEMMA
- A plug-and-cable connection system used on some maker electronics boards to make wiring simpler. If a product uses STEMMA, you need the matching cable or connector type to plug it in without soldering.
- STEMMA QT
- A small plug-in connector system for I2C boards that lets you connect compatible sensors and controllers without soldering. It matters because it can make wiring faster and less error-prone, especially when adding several small modules to a project.
Find this product in
Brands
Connectivity
Related Tutorials
Free guides on learn.littlebird.com.au