I am in search of Passive RFID tag which operates at UHF band with internal / external temperature sense feature.
In datasheet of SL3S4011 it is mentioned as,
For I2C operation, the UCODE I2C has to be supplied externally via the VDD pin. Do we need to connect external power to VDD pin or else the VDD pin can source external power through RF Energy harvesting.
Since my requirement is passive can you suggest any RFID UCODE chip that can source power to micro controller and has SPI / I2C interface.