论文信息 - An energy-efficient reconfigurable readout circuit for resonant sensors based on ring-down measurement

An energy-efficient reconfigurable readout circuit for resonant sensors based on ring-down measurement

This paper presents a novel readout circuit for micro-mechanical resonant sensors. To determine the sensor's resonance frequency and quality factor, the sensor is briefly excited, after which the exponentially-decaying ring-down current produced by a piezoelectric transducer is read out by an auto-zeroed trans-impedance amplifier (TIA). An auto-zeroed comparator then detects zero- and level-crossings for frequency counting and quality factor measurement. A new circuit topology is proposed to reduce errors due to leakage currents. Moreover, a reconfigurable TIA enhances the circuit's flexibility. A prototype chip has been implemented in a 0.35 μm CMOS process. Experimental results obtained using a silicon-nitride clamped-clamped beam resonator are in good agreement with results obtained using conventional impedance analysis. In a measurement time of 2 ms, the circuit achieves a 50 ppm detection limit in resonance frequency, 5 times better than prior work, while consuming only 31.5 μA from a 3.3 V supply.

[1] Bengt Herbert Kasemo,et al. A simple setup to simultaneously measure the resonant frequency and the absolute dissipation factor of a quartz crystal microbalance , 1996 .

[2] Mercedes Crego-Calama,et al. Enhanced sensitivity volatile detection with low power integrated micromechanical resonators. , 2010, Lab on a chip.

[3] Robert Puers,et al. Piezoelectric transduction of flexural modes in pre-stressed microbeam resonators , 2014 .

[4] M. Vandecasteele,et al. Toward a Miniaturized Low-Power Micromechanical Electronic Nose , 2012, IEEE Sensors Journal.

[5] K. Hayatleh,et al. Using the ‘T’ feedback network with the current feedback operational amplifier , 2004 .

[6] Fredrik Höök,et al. Quartz crystal microbalance setup for frequency and Q‐factor measurements in gaseous and liquid environments , 1995 .

[7] Z. Zeng,et al. An energy-efficient readout circuit for resonant sensors based on ring-down measurement. , 2013, The Review of scientific instruments.

[8] Craig A. Grimes,et al. Time domain characterization of oscillating sensors: Application of frequency counting to resonance frequency determination , 2002 .

[9] Craig A. Grimes,et al. Threshold-crossing counting technique for damping factor determination of resonator sensors , 2004 .

[10] Julia Pettine,et al. Power-efficient readout circuit for miniaturized electronic nose , 2012, 2012 IEEE International Solid-State Circuits Conference.