Abstract:
An RF-powered transponder with temperature and photo sensors is designed and fabricated for environmental monitoring. The transponder gathers power from external ISM (860...Show MoreMetadata
Abstract:
An RF-powered transponder with temperature and photo sensors is designed and fabricated for environmental monitoring. The transponder gathers power from external ISM (860-960MHz) band RF signal and senses ambient temperature and light. It contains a supply voltage generator, a temperature-compensated ring oscillator, an oversampling synchronizer, a PTAT temperature sensor and an abrupt transition buffered photo sensor. Its internal clock frequency has variation less than 7% for 1.5-V supply voltage and 90/spl deg/C temperature change. The transponder occupies 0.4mm/sup 2/ with 0.25-/spl mu/m CMOS process and dissipates only 5.14-/spl mu/W during active state.
Date of Conference: 12-16 September 2005
Date Added to IEEE Xplore: 05 December 2005
Print ISBN:0-7803-9205-1
Print ISSN: 1930-8833