Sensor-enabled RFID tags extend wireless data-logging
ams AG has launched new next-generation sensor-enabled RFID tags for medical, automotive safety and other applications where temperature, physiological or environmental data is required. The new devices, the SL13A and SL900A, enable a simple, low-cost implementation of a new class of wireless data-logging applications. The SL13A is an ISO15693-compliant tag for use with near field communications (NFC-V) and high-frequency radio-frequency identification (HF RFID) readers. The SL900A is an EPC Gen 2 Class 3 tag for use with RFID readers.
The devices include an on-board temperature sensor, an interface to an external sensor, and can operate in passive (batteryless) mode. In this mode, the tag harvests energy from a reader’s broadcast, using the power to read the temperature or data from an external sensor, and transmits the information back to the reader together with a unique ID. The data is time-stamped by the reader.
The SL13A and SL900A can be powered by a single-cell or 3V battery. In battery-assisted passive (BAP) mode, the tag’s on-board real-time clock is enabled, and can be used to trigger periodic sensor readings. Up to 762 (SL13A) or 841 (SL900A) time-stamped events may be saved in the on-chip EEPROM, from where they may be read when the device is in range of a reader.
Both the SL13A and SL900A feature a serial peripheral interface for connection to a microcontroller. They can operate from a power supply ranging from 1.2V to 3.6V. The tags provide for very long battery life, drawing a typical 1.6µA in stand-by mode with the real-time clock running. The on-board temperature sensor is accurate to up to 0.5%.
For medical equipment OEMs, the SL13A and SL900A offer opportunities for new applications, such as an NFC sensor tag that can be safely and easily implanted or swallowed, enabling patients to monitor specific physiological conditions around the clock, reading data simply by holding an NFC-enabled phone or tablet close to the body.