The SL13A and SL900A sensor-enabled RFID tags, developed by ams AG, extend wireless data logging to applications that require temperature, physiological, and environmental data. 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, an EPC Gen 2 Class 3 tag, can be used with RFID readers. They include an on-board temperature sensor and an interface to an external sensor. The tags operate in passive (battery-less) mode, in which they harvest energy from a reader’s broadcast, using the power to read the temperature or data from an external sensor. Then the information is transmitted back to the reader together with a unique ID. The tags also can be powered by a single-cell or 3-V battery. Battery-assisted passive mode enables the tag’s on-board real-time clock, which can be used to trigger periodic sensor readings. Up to 762 (SL13A) or 841 (SL900A) time-stamped events are able to be saved in the on-chip EEPROM.