An Analog Front End Circuit Design Of The Contactless RFID

The 13.56 MHz analog front-end circuit for ISO/IEC 15693-compatible radio frequency identification (RFID) transponder IC presented in this paper converts RF power to DC and the protection circuits function to limit RF voltage to a safe level. The chip also generates a Power on Reset signal for digital circuits. The clock extraction circuit can extract clock from the RF power and use it for the RFID system. The demodulation circuit can demodulate the data from the interrogator by 10% or 100% ASK modulation, and the interrogator completes the process that transferring the data to transponder. The transponder sends data back to the interrogator by load modulation technology. The low power analog front-end circuits to achieve longer operation distance. An inductive coupling simulation model for 13.56 MHz RFID system is presented, with simulation results showing that the transponder operates over a wide range of electromagnetic field strength from H min (150 mA/ m) to H max(5 A/ m),and the analog front-end circuit works normally.