Low noise μWatt interface circuits for wireless implantable real-time digital blood pressure monitoring

A wireless implantable blood pressure monitoring microsystem employs an MEMS capacitive pressure sensor, which converts pressure signal to a capacitance change with a sensitivity of approximately 0.7 fF/mmHg. Low-noise muWatt correlated-double-sampling capacitance-to-voltage interface converter followed by an 11-bit cyclic ADC further converts the capacitive signal to a digital output for data processing and telemetry. The prototype microsystem achieves a resolution of 0.1 mmHg over a 1 kHz bandwidth with a dynamic range of 59 dB and consumes 18 muA from a 2 V supply.

[1]  Yoh-Han Pao,et al.  Naturally occurring variation in cardiovascular traits among inbred mouse strains. , 2002, Genomics.

[2]  Jiangang Du,et al.  High-temperature single-crystal 3C-SiC capacitive pressure sensor , 2004, IEEE Sensors Journal.

[3]  D.J. Young,et al.  Wireless less-invasive blood pressure sensing microsystem for small laboratory animal in vivo real-time monitoring , 2008, 2008 5th International Conference on Networked Sensing Systems.

[4]  B. Wooley,et al.  A 1.8-V digital-audio sigma-delta modulator in 0.8-μm CMOS , 1997, IEEE J. Solid State Circuits.

[5]  William C. Tang,et al.  Surface Micromachined Capacitive Differential Pressure Sensor With Lithographically-defined Silicon Diaphragm , 1995, Proceedings of the International Solid-State Sensors and Actuators Conference - TRANSDUCERS '95.

[6]  Gabor C. Temes,et al.  Design-oriented estimation of thermal noise in switched-capacitor circuits , 2005, IEEE Transactions on Circuits and Systems I: Regular Papers.

[7]  David A. Johns,et al.  Analog Integrated Circuit Design , 1996 .

[8]  Peng Cong,et al.  Implantable blood pressure monitoring of small animal for advanced biological research , 2005, The 13th International Conference on Solid-State Sensors, Actuators and Microsystems, 2005. Digest of Technical Papers. TRANSDUCERS '05..

[9]  B. A. Wooley,et al.  A 1.8-V digital-audio sigma-delta modulator in 0.8-/spl mu/m CMOS , 1997 .

[10]  Alan B. Grebene,et al.  Analog Integrated Circuit Design , 1978 .