The ST25DV04K-IER6T3 is a 4 Kbit dynamic NFC/RFID tag IC with dual RF (ISO/IEC 15693, NFC Forum Type 5) and I²C interfaces. It features flexible, password-protected EEPROM areas, a 256-byte Mailbox buffer for fast RF-to-I²C data exchange, energy harvesting capability, and a programmable GPO for event signalling. Supplied in an 8-pin TSSOP package, it is ideal for IoT, smart sensors, and authentication applications.