The ST25DV04K, ST25DV16K and ST25DV64K devices are NFC RFID tags offering respectively 4 Kbit, 16 Kbit, and 64 Kbit of electrically erasable programmable memory (EEPROM). ST25DV04K, ST25DV16K and ST25DV64K offer two interfaces. The first one is an I2C serial link and can be operated from a DC power supply. The second one is a RF link activated when ST25DV04K, ST25DV16K or ST25DV64K act as a contactless memory powered by the received carrier electromagnetic wave. In I2C mode, the ST25DV04K, ST25DV16K and ST25DV64K user memory contains up to 512 bytes, 2048 bytes and 8192 bytes, which could be split in 4 flexible and protectable areas. In RF mode, following ISO/IEC 15693 or NFC forum type 5 recommendations, ST25DV04K, ST25DV16K and ST25DV64K user memory contains respectively up to 128 blocks, 512 blocks and 2048 blocks of 4 bytes which could be split in 4 flexible and protectable areas.