Title :
A 2.3μW wireless intraocular pressure/temperature monitor
Author :
Shih, Yi-Chun ; Shen, Tueng ; Otis, Brian
Author_Institution :
Dept. of Ophthalmology, Univ. of Washington, Seattle, WA, USA
Abstract :
We present the design of an ultra-low power, wireless capacitance/temperature sensing device for continuous intraocular pressure monitoring. The device is wirelessly powered and demonstrates a power consumption of 2.3μW at 1.5V during continuous reading. The chip converts both capacitance and temperature to frequency using a time-interleaved relaxation oscillator, which modulates RF backscatter to a reader for computation of measured samples. The chip exhibits measured capacitance and temperature standard deviations of 1.4fF and 0.4°C, respectively.
Keywords :
capacitance measurement; eye; patient monitoring; pressure sensors; temperature sensors; wireless sensor networks; RF backscatter; capacitance sensing device; intraocular temperature monitor; power 2.3 muW; time interleaved relaxation oscillator; wireless intraocular pressure monitor; Capacitance; Oscillators; Power demand; Radio frequency; Temperature measurement; Temperature sensors;
Conference_Titel :
Solid State Circuits Conference (A-SSCC), 2010 IEEE Asian
Conference_Location :
Beijing
Print_ISBN :
978-1-4244-8300-6
DOI :
10.1109/ASSCC.2010.5716599
