ams supplies two RFID tags which feature on-board sensing capabilities, enabling designers to combine wireless identification with environmental sensing in a single device. The SL13A and SL900A support 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 accurate to ±0.5% and an interface to an external sensor, which may be used to log environmental conditions such as humidity, air pressure or ambient light.
Both devices 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 may be time-stamped by the reader.
The SL13A and SL900A can also be powered by a single-cell or 3V battery. In battery-assisted passive mode, the tag’s onboard real-time clock is enabled, and can be used to trigger periodic sensor readings. The tags provide for very long battery life, drawing a typical 1.6µA in stand-by mode with the real-time clock running.
Up to 762 (SL13A) or 841 (SL900A) timestamped 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.
The combination of a sensor interface, NFC compatibility and support for passive mode offers designers the opportunity to invent new kinds of wireless data-logging applications, or to find better ways to implement existing datalogging systems.
For medical equipment OEMs, the SL13A and SL900A offer opportunities for exciting new applications, such as an NFC sensor tag that can be safely implanted or swallowed. This enables patients to monitor physiological conditions around the clock, reading data simply by holding an NFC-enabled phone or tablet close to the body.
- Patient monitoring
- Building control
- Automotive safety equipment
- Transportation and logistics
- Inventory and stock control
- Harvests up to 5mA from reader’s RF emissions
- Operating temperature range:
- — SL13A: -40°C to 110°C
- — SL900A: -40°C to 125°C