On-Chip Noise Sensor for Integrated Circuit Susceptibility Investigations

page number: 12International audienceWith the growing concerns about electromagnetic compatibility of integrated circuits, the need for accurate prediction tools and models to reduce risks of non-compliance becomes critical for circuit designers. However, on-chip characterization of noise is still necessary for model validation and design optimization. Although different on-chip measurement solutions have been proposed for emission issue characterization, no on-chip measurement methods have been proposed to address the susceptibility issues. This paper presents an on-chip noise sensor dedicated to the study of circuit susceptibility to electromagnetic interferences. A demonstration of the sensor measurement performances and benefits is proposed through a study of the susceptibility of a digital core to conducted interferences. Sensor measurements ensure a better characterization of actual coupling of interferences within the circuit and a diagnosis of failure origins

The Evaluation of Potentiostats: Electrochemical Detection Devices

This study evaluated the performance of three types of potentiostats; EmStat, CheapStat and UTMStat. EmStat is the smallest potentiostat available in the market. CheapStat is an open-source potentiostat suitable for educational applications. In addition, UTMStat is the extension of CheapStat, which was designed to overcome few weaknesses of CheapStat such as the input controller/ switch and data storage handling of the cyclic voltammogram. The cyclic voltammetry and amperometry measurements of ions ferrocyanide ([Fe(CN)6]4−) and chloride (Cl-) were carried out for each potentiostat. EmStat potentiostat is not only able to detect but also to measure ferrocyanide and chloride ions. However, CheapStat and UTMStat are only able to detect and measure ferrocyanide ions. The experiment is unable to be conducted due to limitation of waveform selection on both devices. Nevertheless, CheapStat and UTMStat could provide a reliable measurement to realize miniaturized lab-on-chip applications as shown in this study

Design and Development of Smart Brain-Machine-Brain Interface (SBMIBI) for Deep Brain Stimulation and Other Biomedical Applications

Machine collaboration with the biological body/brain by sending electrical information back and forth is one of the leading research areas in neuro-engineering during the twenty-first century. Hence, Brain-Machine-Brain Interface (BMBI) is a powerful tool for achieving such machine-brain/body collaboration. BMBI generally is a smart device (usually invasive) that can record, store, and analyze neural activities, and generate corresponding responses in the form of electrical pulses to stimulate specific brain regions. The Smart Brain-Machine-Brain-Interface (SBMBI) is a step forward with compared to the traditional BMBI by including smart functions, such as in-electrode local computing capabilities, and availability of cloud connectivity in the system to take the advantage of powerful cloud computation in decision making. In this dissertation work, we designed and developed an innovative form of Smart Brain-Machine-Brain Interface (SBMBI) and studied its feasibility in different biomedical applications. With respect to power management, the SBMBI is a semi-passive platform. The communication module is fully passive—powered by RF harvested energy; whereas, the signal processing core is battery-assisted. The efficiency of the implemented RF energy harvester was measured to be 0.005%. One of potential applications of SBMBI is to configure a Smart Deep-Brain-Stimulator (SDBS) based on the general SBMBI platform. The SDBS consists of brain-implantable smart electrodes and a wireless-connected external controller. The SDBS electrodes operate as completely autonomous electronic implants that are capable of sensing and recording neural activities in real time, performing local processing, and generating arbitrary waveforms for neuro-stimulation. A bidirectional, secure, fully-passive wireless communication backbone was designed and integrated into this smart electrode to maintain contact between the smart electrodes and the controller. The standard EPC-Global protocol has been modified and adopted as the communication protocol in this design. The proposed SDBS, by using a SBMBI platform, was demonstrated and tested through a hardware prototype. Additionally the SBMBI was employed to develop a low-power wireless ECG data acquisition device. This device captures cardiac pulses through a non-invasive magnetic resonance electrode, processes the signal and sends it to the backend computer through the SBMBI interface. Analysis was performed to verify the integrity of received ECG data

Advanced sensors technology survey

This project assesses the state-of-the-art in advanced or 'smart' sensors technology for NASA Life Sciences research applications with an emphasis on those sensors with potential applications on the space station freedom (SSF). The objectives are: (1) to conduct literature reviews on relevant advanced sensor technology; (2) to interview various scientists and engineers in industry, academia, and government who are knowledgeable on this topic; (3) to provide viewpoints and opinions regarding the potential applications of this technology on the SSF; and (4) to provide summary charts of relevant technologies and centers where these technologies are being developed

The potential of microelectrode arrays and microelectronics for biomedical research and diagnostics

Planar microelectrode arrays (MEAs) are devices that can be used in biomedical and basic in vitro research to provide extracellular electrophysiological information about biological systems at high spatial and temporal resolution. Complementary metal oxide semiconductor (CMOS) is a technology with which MEAs can be produced on a microscale featuring high spatial resolution and excellent signal-to-noise characteristics. CMOS MEAs are specialized for the analysis of complete electrogenic cellular networks at the cellular or subcellular level in dissociated cultures, organotypic cultures, and acute tissue slices; they can also function as biosensors to detect biochemical events. Models of disease or the response of cellular networks to pharmacological compounds can be studied in vitro, allowing one to investigate pathologies, such as cardiac arrhythmias, memory impairment due to Alzheimer's disease, or vision impairment caused by ganglion cell degeneration in the retin

Investigation of using potentiostats and microfluidic devices for continuous ions detection

In the light of the importance of the bedside patient monitoring system, a miniaturized, flexible, versatile, disposable and cost effective bedside patient continuous monitoring system is essential. Therefore, this research addresses the development of a cost effective and miniaturize continuous monitoring system. For electrochemical analysis, three potentiostats were used: EmStat, CheapStat and in house UTMStat. For lab-on-chip system, two models were proposed and their electrochemistry and pumping characteristics were studied. The 2 layers detection zone was developed through fused filament technology and replication moulding technique with a screen printed electrode attached together. It achieved the maximum flow rate of 0.30405 ml/min with resonance frequency of 20 Hz in micropump reverse direction. With the maximum frequency, the highest oxidation peak current of 15.86176 |iA in cyclic voltammetry measurement was achieved by 10 mM ferrocyanide ions at potential 0.25 V. The monolithic microfluidic device was developed through sticker masks fabrication and replication moulding technique with two screen printed electrodes attached beneath the inlets and the outlets of the micropump. It achieved the maximum flow rate of 0.19693 ml/min with resonance frequency of 10 Hz in micropump forward direction. With the maximum frequency, the highest oxidation peak current of 28.32518 |xA in cyclic voltammetry measurement was achieved by 10 mM ferrocyanide ions at potential 0.32 V. Additionally, the electrochemical investigation was extended by measuring the cyclic voltammetry measurements of chloride ions from a mixture by using EmStat and CheapStat. The highest oxidation peak was observed at 61.26875 |jA and 1.04400 |±A by using EmStat and CheapStat respectively at potential 0.13 V. Specifically, the monolithic microfluidic device is well integrated in lab-on-chip system with the advantage of miniaturize with the dimensions of 41 mm x 26 mm, cost effective by using sticker masks fabrication and replication moulding technique, disposability since it is inexpensive and meant for biomedical analysis, flexibility where it can be used for other ions detection just by changing the screen printed electrode and can measure the data during pumping. This research successfully provides an alternative approach for continuous monitoring of ferrocyanide and chloride ions detection via cyclic voltammetry and amperometry measurements

Advances in Microelectronics for Implantable Medical Devices

Implantable medical devices provide therapy to treat numerous health conditions as well as monitoring and diagnosis. Over the years, the development of these devices has seen remarkable progress thanks to tremendous advances in microelectronics, electrode technology, packaging and signal processing techniques. Many of today’s implantable devices use wireless technology to supply power and provide communication. There are many challenges when creating an implantable device. Issues such as reliable and fast bidirectional data communication, efficient power delivery to the implantable circuits, low noise and low power for the recording part of the system, and delivery of safe stimulation to avoid tissue and electrode damage are some of the challenges faced by the microelectronics circuit designer. This paper provides a review of advances in microelectronics over the last decade or so for implantable medical devices and systems. The focus is on neural recording and stimulation circuits suitable for fabrication in modern silicon process technologies and biotelemetry methods for power and data transfer, with particular emphasis on methods employing radio frequency inductive coupling. The paper concludes by highlighting some of the issues that will drive future research in the field