SAN FRANCISCO Researchers from the European Holst Center said their 64-bit, inductively-coupled, passive RFID tag achieved a record 780-bit/second data readout.
In a presentation at the International Solid State Circuit Conference here, they said the performance over a distance of 10 cm approaches the requirements for tagging products and other items.
The tag represents a five-fold increase in bit rate performance compared to state-of-the-art plastic RFIDs. The achievement could pave the way for low-cost, high-volume RFID tags to replace bar codes.
The 64-bit RFID consists of a low-cost inductive antenna, capacitor, plastic rectifier and plastic circuit, all on foil. The antenna operates at 13.56 MHz and powers up the organic rectifier with an ac voltage at that frequency. From this voltage, the rectifier generates dc supply voltage for the 64-bit organic transponder chip. The chip drives the modulation transistor between on and off states with a 64-bit code sequence.
The foil used for the transponder chip was processed with organic electronics technology provided by Holst Center partner Polymer Vision.
Organic vertical diodes are used in rectifiers because they outperform organic transistors at frequencies at and above 13.56 MHz. At an RF magnetic field strength of 1.26amps/meter, the rectifier generates an internal transponder supply voltage of 14V. At this voltage, the 64-bit code is read out at 787 bits/second.
The 64-bit transponder chip uses organic bottom-gate, p-type, Pentacene thin-film transistors from a soluble precursor route. It includes about 400 transistors, making it significantly smaller than previous designs.
The Holst Center was founded in 2005 by the Belgian research center IMEC and its Dutch counterpart TNO. It focuses on wireless microsystems and systems-in-foil.