Wireless sensing by means of passive multistandard RFID tags

This paper presents a generic sensor interface built in a 0.13 µm CMOS process capable of being applied in passive HF & UHF RFID Tags without any additional power supply. The sensor interface contains an ultra low-power successive approximation ADC that uses the capacitive charge redistribution technique for its integrated DAC. An on-chip temperature sensor and up to three additional sensor signals can be applied to the ADC. A conversion rate of 100 kSps is reached while consuming less than 1.5 µA at 0.9 Volt supply voltage.