Diego Ruben Barrettino | EPFL Graph Search

Diego Barrettino (S’93–M’98–SM’06) received the Dipl.-Ing. degree in Electronic Engineering from the University of Buenos Aires, Argentina, in 1997, and the Ph.D. degree in Electrical Engineering from the Swiss Federal Institute of Technology Zurich (ETHZ) in 2004.

He worked at Allegro MicroSystems Inc., from 1997 to 2000, where he was an Analog IC Designer of Hall-effect magnetic sensors. From 2000 to 2004, he was a Ph.D. student and Research Assistant at ETHZ, where he designed chemical and mechanical sensors. In 2004, he moved to the USA where he designed biomedical devices first as a Post-Doctoral Research Associate in the University of Washington, and then as an Assistant Professor in the University of Hawaii. In 2006, he returned to Europe where he joined the Swiss Federal Institute of Technology Lausanne (EPFL) as a Senior Research Scientist for the design and development of biosensors using organic nanotransistors. From 2007 to 2009, he was a Senior Lecturer in the University of Glasgow, U.K., and in the University College Cork, Republic of Ireland, where he designed ultra-low power biomedical devices. From 2009 to 2017, he was Full Professor and Head of the Laboratory of Microelectronics, Bioelectronics and Sensor Systems (LMBS) at the University of Applied Sciences of Southern Switzerland (SUPSI), where he designed smart contact lenses and eye implants. In 2017, he joined both the Lucerne University of Applied Sciences (HSLU) and EPFL as a part-time Senior Research Scientist to continue his work on smart sensor systems.

His research interests are in the fields of physical, chemical, and biomedical microsensors; sensor fusion algorithms; analog and mixed-signal IC design; MEMS; embedded systems; avionics and bioelectronics.

Diego Barrettino is a senior member of the Institute of Electrical and Electronics Engineers (IEEE), a member of the American Institute of Aeronautics and Astronautics (AIAA) and a member of the American Association for the Advancement of Science (AAAS).

A Capacitively-Coupled Chopper Instrumentation Amplifier for Implantable Bridge Sensor Systems

Diego Ruben Barrettino, Mustafa Besirli, Catherine Dehollain, Marco Mattavelli, Kerim Türe

This paper presents an energy and area efficient capacitively-coupled chopper instrumentation amplifier (CCIA) dedicated to implantable bridge sensor systems. Chopper stabilization is employed to decrease its offset and 1/f noise and the resulting ripple due to the up-modulated offset and 1/f noise is suppressed by a switched-capacitor ripple reduction loop. The gain of the instrumentation amplifier is defined by a programmable capacitive feedback network with a gain range from 40 V/V to 116 V/V, which is suitable for use with bridge sensors having different output voltages. The proposed CCIA has been fabricated in a standard 0.18 mu m CMOS process. It achieves an input noise of 88.2 nV/root Hz, a worst-case input offset of 5 mu V, and an output ripple of less than 185 mu V. The CCIA occupies only 0.17 mm(2) chip area and draws 3.3 mu A current from a 1.2 V supply.

IEEE2022

An Energy-Efficient Bridge-to-Digital Converter for Implantable Pressure Monitoring Systems

Diego Ruben Barrettino, Mustafa Besirli, Catherine Dehollain, Franco Maloberti, Marco Mattavelli, Kerim Türe

This paper presents an energy-efficient, duty-cycled, and spinning excitation bridge-to-digital converter (BDC) designed for implantable pressure sensing systems. The circuit provides the measure of the pulmonary artery pressure that is particularly relevant for the monitoring of heart failure and pulmonary hypertension patients. The BDC is made of a piezoresistive pressure sensor and a readout integrated circuit (IC) that comprises an instrumentation amplifier (IA) followed by an analog-to-digital converter (ADC). The proposed design spins both the bridge excitation and the ADC’s sampling input voltages simultaneously and exploits duty cycling to reduce the static power consumption of the bridge sensor and IA while cancelling the IA’s offset and 1/f noise at the same time. The readout IC has been designed and fabricated in a standard 180-nm CMOS process and achieves 8.4 effective number of bits (ENOB) at 1 kHz sampling rate while drawing 0.53 µA current from a 1.2 V supply. The BDC, built with the readout IC and a differential pressure sensor having 5 kΩ bridge resistances, achieves 0.44 mmHg resolution in a 270 mmHg pressure range at 1 ms conversion time. The current consumption of the bridge sensor by employing duty cycling is reduced by 99.8% thus becoming 0.39 µA from a 1.2 V supply. The total conversion energy of the pressure sensing system is 1.1 nJ, and achieves a figure-of-merit (FoM) of 3.3 pJ/conversion, which both represent the state of the art.

2022

An Implantable Inductive Sensor for Direct and Continuous Monitoring of the Pulmonary Artery Cross-Sectional Area

Diego Ruben Barrettino, Mustafa Besirli, Catherine Dehollain, Marco Mattavelli, Kerim Türe

This paper presents a novel method for the measure of the cross-sectional area (CSA) of an artery to be used for the direct and continuous (24/7) monitoring of cardiac output (CO). The method is based on the inductance change of an anchoring loop mounted on a miniaturized system implanted in a section of the pulmonary artery. The inductive sensor comprises an inductive readout circuit and a conductive anchoring loop, which changes its inductance according to the deformation of the artery and can be correlated to the diameter and CSA of the artery section. Direct and periodic measurement of the CSA can improve the accuracy of CO monitoring in heart failure patients. An oscillator-based inductive readout IC was realized in a 180-nm CMOS process and the anchoring loop was implemented by a nitinol wire. The readout IC achieves 0.42 nH inductance resolution in a range from 181 nH to 681 nH and draws 39.7 μA to 51.2 μA current from a 1.2 V supply. The correlation between the artery diameter and loop inductance is demonstrated and the sensor achieves 0.24 mm resolution in a diameter range from 20 mm to 30 mm, a factor of four higher than the lateral resolution of echocardiography.

IEEE2022