Jordi Colomer-Farrarons

Power-Conditioning Circuitry for a Self-Powered System Based on Micro PZT Generators in a 0.13-

The concept and design of a power-conditioning circuit for an autonomous low-power system-in-package (SiP) is presented in this paper. The SiPs main power source is based on the use of micropiezoelectric generators. The electrical model of the power source, which has been obtained based on experimental measurements and implemented on Cadence Analog Artists Spectre simulation environment, is explained. The model has been used to simulate the power source with the power-conditioning electronics over the entire design process. Finally, the simulated and experimental results of the developed integrated power circuits, which are formed by a rectifier and a low-power bandgap reference voltage source to define the threshold voltage for the closed-loop regulation process, are also shown. These circuits have been designed using a commercial 0.13-mum technology from ST Microelectronics through the multi-projects circuits (CMP) techniques of informatics and microelectronics for integrated systems architecture (TIMA) service.

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A multiharvesting system conception focused on low-voltage (up to 2.5 V) and low-power applications is presented and validated as a point-of-view system. Using just this application-specified integrated circuit, with a total quiescent power consumption of 160 μW, the harvesting system is able to collect and manage energy from different power sources, such as solar light (indoor environment), vibration (low-voltage piezoelectric generators), and electromagnetic induction (operating with a carrier frequency of 13.56-MHz regulated band). The maximum total power harvested with the addition of the three harvesting sources is around 6.4 mW, for the operating conditions defined by a PZT at 7 m/s2 at 80 Hz, 1500 lx for a laboratory illumination, and 200 mW emitted by a base transmitter at 25-mm distance between coils. A broad and detailed description of all low-power-consumption circuits involved in the multiharvesting system is described, emphasizing their design for low-voltage and low-power applications.

Low-Voltage Low-Power Technology

Bacteria concentration and detection is time-consuming in regular microbiology procedures aimed to facilitate the detection and analysis of these cells at very low concentrations. Traditional methods are effective but often require several days to complete. This scenario results in low bioanalytical and diagnostic methodologies with associated increased costs and complexity. In recent years, the exploitation of the intrinsic electrical properties of cells has emerged as an appealing alternative approach for concentrating and detecting bacteria. The combination of dielectrophoresis (DEP) and impedance analysis (IA) in microfluidic on-chip platforms could be key to develop rapid, accurate, portable, simple-to-use and cost-effective microfluidic devices with a promising impact in medicine, public health, agricultural, food control and environmental areas. The present document reviews recent DEP and IA combined approaches and the latest relevant improvements focusing on bacteria concentration and detection, including selectivity, sensitivity, detection time, and conductivity variation enhancements. Furthermore, this review analyses future trends and challenges which need to be addressed in order to successfully commercialize these platforms resulting in an adequate social return of public-funded investments.

A Multiharvested Self-Powered System in a Low-Voltage Low-Power Technology

We present a small, compact and portable device for point-of-care instantaneous early detection of anemia. The method used is based on direct hematocrit measurement from whole blood samples by means of impedance analysis. This device consists of a custom electronic instrumentation and a plug-and-play disposable sensor. The designed electronics rely on straightforward standards for low power consumption, resulting in a robust and low consumption device making it completely mobile with a long battery life. Another approach could be powering the system based on other solutions like indoor solar cells, or applying energy-harvesting solutions in order to remove the batteries. The sensing system is based on a disposable low-cost label-free three gold electrode commercial sensor for 50 μL blood samples. The device capability for anemia detection has been validated through 24 blood samples, obtained from four hospitalized patients at Hospital Clínic. As a result, the response, effectiveness and robustness of the portable point-of-care device to detect anemia has been proved with an accuracy error of 2.83% and a mean coefficient of variation of 2.57% without any particular case above 5%.

Combined Dielectrophoresis and Impedance Systems for Bacteria Analysis in Microfluidic On-Chip Platforms

Preface / Abstract. Abbreviations. 1 Introduction. 1.1 Energy Harvesting in Human and Non-Human Activities. 1.2 BioSensors. 1.3 Circuits for Three Electrodes BioSensors. 1.4 Contribution of this Book. 1.5 Outline of the Book. 1.6 References. 2 Energy Harvesting (Multi Harvesting Power Chip). 2.1 Multi Harvesting Power Chip (MHPC). 2.2 Solar and Inductive Power Harvesting. 2.3 Piezoelectric Harvesting. 2.4 Chapter Conclusions. 2.5 References. 3 Biomedical Integrated Instrumentation. 3.1 General Introduction to Biomedical Instrumentation. 3.2 Electrochemical Biosensors. 3.3 Potentiostat (Sensor Instrumentation). 3.4. Low-Frequency Lock-In Amplifier. 3.5 Biotelemetry for Implanted Devices. 3.6 Chapter Conclusions. 3.7 References. 4 CMOS Front-End Architecture for In-Vivo Biomedical Subcutaneous Detection Devices. 4.1 Introduction. 4.2 Front-End General Architecture. 4.3 Prototypes Design and Results. 4.4 Chapter Conclusions. 4.5 References. 5 Conclusions and Future Work. 5.1 Conclusions. 5.2 Future Work. Appendix 1. Appendix 2. Appendix 3.

An Instantaneous Low-Cost Point-of-Care Anemia Detection Device

The present paper reports a bacteria autonomous controlled concentrator prototype with a user‐friendly interface for bench‐top applications. It is based on a microfluidic lab‐on‐a‐chip and its associated custom instrumentation, which consists of a dielectrophoretic actuator, to preconcentrate the sample, and an impedance analyzer, to measure concentrated bacteria levels. The system is composed of a single microfluidic chamber with interdigitated electrodes and an instrumentation with custom electronics. The prototype is supported by a real‐time platform connected to a remote computer, which automatically controls the system and displays impedance data used to monitor the status of bacteria accumulation on‐chip. The system automates the whole concentrating operation. Performance has been studied for controlled volumes of Escherichia coli samples injected into the microfluidic chip at constant flow rate of 10 μL/min. A media conductivity correcting protocol has been developed, as the preliminary results showed distortion of the impedance analyzer measurement produced by bacterial media conductivity variations through time. With the correcting protocol, the measured impedance values were related to the quantity of bacteria concentrated with a correlation of 0.988 and a coefficient of variation of 3.1%. Feasibility of E. coli on‐chip automated concentration, using the miniaturized system, has been demonstrated. Furthermore, the impedance monitoring protocol had been adjusted and optimized, to handle changes in the electrical properties of the bacteria media over time.

A CMOS Self-Powered Front-End Architecture for Subcutaneous Event-Detector Devices

The first part of this paper reviews the current development and key issues on implantable multi-sensor devices for in vivo theranostics. Afterwards, the authors propose an innovative biomedical multisensory system for in vivo biomarker monitoring that could be suitable for customized theranostics applications. At this point, findings suggest that cross-cutting Key Enabling Technologies (KETs) could improve the overall performance of the system given that the convergence of technologies in nanotechnology, biotechnology, micro&nanoelectronics and advanced materials permit the development of new medical devices of small dimensions, using biocompatible materials, and embedding reliable and targeted biosensors, high speed data communication, and even energy autonomy. Therefore, this article deals with new research and market challenges of implantable sensor devices, from the point of view of the pervasive system, and time-to-market. The remote clinical monitoring approach introduced in this paper could be based on an array of biosensors to extract information from the patient. A key contribution of the authors is that the general architecture introduced in this paper would require minor modifications for the final customized bio-implantable medical device.

Combined dielectrophoretic and impedance system for on-chip controlled bacteria concentration: Application to Escherichia coli

An integrated front-end architecture for in-vivo detection is presented. The system is conceived to be implanted under the human skin. The powering and communication between this device and an external primary transmitter are based on an inductive link. The presented architecture is oriented to two different approaches, defining a true/false alarm system, based on amperometric or impedance biosensors. The particular case of the amperometric sensor is used to validate the architecture in terms of different integrated modules fabricated in a 0.13 ¿m technology. A potentiostat amplifier has been integrated to control an amperometric biosensor as well as a current sensing method based on a transimpedance amplifier is used to measure the current. It is also introduced the electronics designed for the bio-impedance case.

Design of a customized multipurpose nano-enabled implantable system for in-vivo theranostics

A first approach to a portable and compact device for point-of-care (PoC) early instantaneous detection of anemia is described. This device works directly with whole blood samples relying on hematocrit analysis by means of impedance analysis. This device consists of a custom electronic instrumentation, postprocessing software and plug-and-play disposable sensor. The designed electronics are connected to a remote computer, which allows control of the instrumentation and results displaying with a user friendly software panel. The disposable sensor is based on a low-cost label-free three gold electrode commercial sensor for 50-μL volume samples. Forty-eight whole blood samples, randomly collected from hospitalized patients in Hospital Clínic, were used to validate the device capability for anemia detection. Whole blood samples were distributed in two groups: 10 samples for system calibration, and 38 samples for system validation. To calibrate the device, a complete EIS experiment has been performed to get a full impedance spectrum analysis, defining an accurate frequency working range for hematocrit detection. Afterward, we developed a protocol for instant impedance detection to determine the system detection accuracy, sensitivity, and coefficient of variation. As a result, impedance variations between different samples have been detected with less than 2% accuracy error for both impedance magnitude and phase. A hematocrit detection algorithm, relying on impedance analysis, has been developed based on the previous studies. The response, effectiveness, and robustness of the portable PoC device to detect anemia have been proved with an accuracy error of 1.75% and a coefficient of variation of less than 5%.

CMOS front-end architecture for In-Vivo biomedical implantable devices

We describe a novel continuous‐flow cell concentrator microdevice based on dielectrophoresis, and its associated custom‐made control unit. The performances of a classical interdigitated metal electrode‐based dielectrophoresis microfluidic device and this enhanced version, that includes insulator‐based pole structures, were compared using the same setup. Escherichia coli samples were concentrated at several continuous flows and the devices trapping efficiencies were evaluated by exhaustive cell counts. Our results show that pole structures enhance the retention up to 12.6%, obtaining significant differences for flow rates up to 20 μL/min, when compared to an equivalent classical interdigitated electrodes setup. In addition, we performed a subsequent proteomic analysis to evaluate the viability of the biological samples after the long exposure to the actuating electrical field. No Escherichia coli protein alteration in any of the two systems was observed.