A new pseudo asynchronous level crossing analogue-to-digital converter (adc) architecture targeted for low-power, implantable, long-term biomedical sensing applications is presented. In contrast to most of the existing adc designs, proposed design has no digital-to-analogue (dac) and continuous time comparators. Instead, uses an analogue memory cell dynamic The retains signal activity dependent sampling operation by generating events only when input changing. offers advantages smaller chip...

Arc faults in photo-voltaic (Pv) systems are dangerous events and can create huge damage. In order to decrease the number of these events, arc fault detectors used. The advantages here presented detection algorithm relatively low computational demand ability work with most standard analog-digital converter (Adc) contained micro controllers.

A noise analysis of switched-capacitor (SC) circuits is presented that describes the time-averaged second-order statistics cyclostationary processes encountered in such systems. unified framework makes it possible to take into account broadband, as well low-frequency (such flicker), sources by basing modeling for all types on mathematical white-noise model which broadband modeled white and linearly filtered noise. The signal decomposition used different from previous approaches leads simple...

We discuss circuit parameters that limit the precision of basic dynamic current-memory cells. In addition to analyzing current-copying errors caused by finite output conductances current sources and clock-feedthrough (CFT) feedback switches, we analyze noise performance memory cell. To reduce CFT noise, propose a novel based on Miller capacitance-enhancement. Measurement results cells integrated in 1-/spl mu/m CMOS process confirm theoretical findings; with our reduction technique enhanced...

A general relationship between the gains of multiterminal amplifiers is derived. This approach generates a constraint for simultaneous improvement common-mode and power-supply rejection ratio simple operational amplifier. can be relaxed by either adding supplementary input terminal to amplifier circuit or using fully differential design. The method used improve ratios in amplifiers. Several implementations two-stage illustrate this technique.< <ETX...

Long-term electrocardiogram (ECG) signals might suffer from relevant baseline disturbances during physical activity. Motion artifacts in particular are more pronounced with dry surface or esophageal electrodes which dedicated to prolonged ECG recording. In this paper we present a method called wander tracking (BWT) that tracks and rejects strong avoids concurrent saturation of the analog front-end. The proposed algorithm shifts level signal middle dynamic input range. Due fast offset shifts,...

The computation of the reciprocal a numerical value is an important ingredient many algorithms. We present compact hardware architecture to compute reciprocals by two or three Newton-Raphson iterations obtain accuracy IEEE 754 single- and double-precision standard, respectively. estimate initialization specially designed second-order polynomial approximating reciprocal. By using polynomial, we succeed in one single for both, approximation computations as well iterations. Therefore, most...

Long-term electrocardiogram (ECG) often suffers from relevant noise. Baseline wander in particular is pronounced ECG recordings using dry or esophageal electrodes, which are dedicated for prolonged registration. While analog high-pass filters introduce phase distortions, reliable offline filtering of the baseline implies a computational burden that has to be put relation increase signal-to-baseline ratio (SBR). Here, we present graphics processor unit (GPU)-based parallelization method speed...

The emerging application of long-term and high-quality ECG recording requires alternative electrodes to improve the signal quality capability surface skin electrodes. esophageal has potential overcome these limitations but necessitates novel recorder lead designs. electrode material is particular interest, since ensure conflicting requirements like excellent biopotential properties inertness. To this end, materials PEDOT silver-PDMS as well established such stainless steel, platinum, gold,...

Asynchronous level crossing sampling analog-to-digital converters (ADCs) are known to be more energy efficient and produce fewer samples than their equidistantly counterparts. However, as the required threshold voltage is lowered, number of and, in turn, data rate consumed by overall system increases. In this paper, we present a cubic Hermitian vector-based technique for online compression asynchronously sampled electrocardiogram signals. The proposed method computationally compression....

Various commercial and academic tools are available for the synthesis of hardware algorithms. Focusing on signal processing algorithms, we compare efficiency, flexibility usability approaches based widely used Matlab with add-on toolboxes or 3rd-party tools. We use several designs as case studies to investigate effect tool features respect architecture design flexibility. Special emphasis is set designer's freedom choice between different arithmetic operator architectures, pipe-lining versus...

Long-term electrocardiography (ECG) featuring adequate atrial and ventricular signal quality is highly desirable. Routinely used surface leads are limited in sensitivity recording capability impeding complete ECG delineation, i.e. the presence of supraventricular arrhythmias. esophageal might overcome these limitations but requires a dedicated lead system recorder design. To this end, we analysed multiple-lead ECGs with respect to by describing waves as function insertion level,...

Pulse wave velocity has emerged as important diagnostic parameter due to its association with various cardiovascular disorders, such hypertension, vascular aging, and atherosclerosis. Long-term monitoring of pulse can be beneficial in carrying out accurate diagnosis the underlying conditions or even for an early prediction diseases. Doppler radar a promising technology contact-less assessment physiological parameters. In this study, we aimed at: i) first step, assessing feasibility measuring...

A procedure for determining the capacitor values a given integrator-based SC (switched capacitor) network with ratios is presented. limited capacitance area optimally distributed among individual circuit capacitors by minimizing overall spread while simultaneously either sensitivity or noise. Noise in circuits function of ideal design parameters such as and levels technology-dependent describing switches amplifiers. In description noise performance, characteristic point was found which only...

Conventional sigma-delta (ΣΔ) analog-to-digital (Ad) converters are based on an analog ΣΔ modulator followed by a digital filter. In this paper we propose new architecture of first-order that needs no active components. We call "digital-only," and implement with it Ad in Fpga's or directly the software microprocessors. here discuss aspects dynamic behavior proposed structure.

We have developed a Swept-Source Optical Coherence Tomography (Ss-OCT) system with high-speed, real-time signal processing on commercially available Data-Acquisition (DAQ) board Field-Programmable Gate Array (FPGA). The Ss-OCT simultaneously acquires OCT and <i>k</i>-clock reference signals at 500MS/s. From the of each A-scan we extract remap vector for <i>k</i>-space linearization signal. linear but oversampled interpolation is followed by 2048-point FFT, additional auxiliary computations,...

Analytic formulas describing the noise performance due to white of two SC-integrator structures using simple and more sophisticated OTA models are presented. It is shown that an oversimplified modeling can lead underestimating as well overestimating effects. The suggest design rules for reducing in integrator structures. numerical analysis a second-order filter indicates these also hold complex mentioned integrators.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML"...

An approximate measure for the noise performance of integrator-based SC (switched capacitor) filters general order n is developed. The dependent on SC-design parameters such as capacitor ratios and capacitance levels, but not technology-dependent describing switches amplifiers. A simple explicit closed-form expression this derived compared with more complex-and accurate-measures. comparison demonstrates extraordinary accuracy computation presented. important application in optimization...

A hierarchical SC (switched-capacitor) filter design methodology that obtains minimal spread in combination with either sensitivity or noise is discussed. The measure and the are defined by an analytic formula uses only capacitors, ideal switches, amplifiers. An efficient capacitor assignment optimization applied on this high level of abstraction. interpreted as a characteristic point lower abstraction also takes into account technological parameters amplifier noise, transconductances,...