Search results for " ADC"
showing 10 items of 12 documents
Silicon dosimeters based on Floating Gate Sensor: design, implementation and characterization
2020
A rad-hard monolithic dosimeter has been implemented and characterized in a standard 180 nm CMOS technology. The radiation sensor (C-sensor) is based on a Floating Gate (FG) MOS discharge principle. The output current is processed by a current-to-voltage (I/V) interface and then converted by a 5-bit flash ADC. The dosimeter is re-usable (FG can be recharged) and can detect a dose up to 1krad (Si) with a resolution of 30rad (Si) typical over temperature 0 to 85°C range. The ADC allows easy further signal processing for calibration and averaging, etc. The power consumption of C-sensor plus I/V interface is < 2mW from a 5 V power supply. The overall layout area is less than 0.25mm2. The Rad…
Design And Characterization Of Automated Color Sensor System
2017
Abstract The paper presents a color sensor system that can process light reflected from a surface and produce a digital output representing the color of the surface. The end-user interface circuit requires only a 3-bit pseudo flash analog-to-digital converter (ADC) in place of the conventional/typical design comprising ADC, digital signal processor and memory. For scalability and compactness, the ADC was designed such that only two comparators were required regardless of the number of color/wavelength to be identified. The complete system design has been implemented in hardware (bread board) and fully characterized. The ADC achieved less than 0.1 LSB for both INL and DNL. The experimental r…
A topology for multiple generation system with doubly fed induction machines and indirect matrix converter.
2008
In this paper, a new topology for a grid connected generation system based on two double fed induction generators is presented The scheme uses an indirect matrix converter consisting on an input rectifier, a three-to-two matrix converter which provides a DC voltage, and two voltage fed output converters. The input converter is connected to the grid and each of the output converters is connected to the rotor of the corresponding machine. The rotor currents of each generator are vector controlled and unity power factor operation at the indirect matrix converter input is considered. The duty cycles for the input converter are chosen in order to obtain maximum DC link voltage. The duty cycles f…
Difference temperature-to-time electronic interface based on a thermistor-to-generalized impedance converter
2010
Abstract In this work a difference temperature-to-time converter is shown using two thermistors working in a DC generalized impedance converter. Voltage drop in one of the thermistors depends on the temperature difference between them. This voltage is compared with a time varying exponential reference voltage obtaining a time interval at the output circuit with good linear dependence with respect to the input temperature difference. Experimental results are obtained showing a new generalized impedance converter application. The implemented circuit was characterized by a repeatability of 1.0%, a reproducibility of 4.5% and a relative accuracy of 1.3%.
Dynamic modelling of a quadratic DC/DC single-switch boost converter
2017
This manuscript proposes the analysis of a Quadratic Boost Converter (QBC) transformer-less single switch typology. The state space average dynamic model and a constrained state space average model taking into account the mono-directional components of the converter (diodes, switches) have been analyzed. The static gain expression taking into consideration the parasitic elements of the converter and the small-signal transfer function of the QBC typology under study has been obtained. A sensitivity analysis has shown a high variation of the gain versus duty-cycle and of the derivative gain versus parasitic parameters of the converter in the range of the duty-cycle from 0.6 to 0.8 which is ra…
Multi-scale analysis of apparent diffusion coefficient (ADC) predicts cervical nodal status in patients with head and neck squamous cell carcinoma
2013
The study assess multi-scale diffusion parameters (median volumetric nodal region of interest values, inter-voxel histogram distributions, and intra-voxel diffusion heterogeneity as assessed by the stretched exponential model) as classifiers of nodal status in patients with head and neck squamous cell carcinoma (SCC). Low b value (0, 50, 100) derived nodal ADC (perfusion sensitive) was the key parameter facilitating discrimination of metastatic from benign nodes in patients with head and neck SCC. The stretched exponential derived α value together with histogram features of ADC provide an accurate decision tree model for classification of nodal disease.
Maximum likelihood ADC parameter estimates improve selection of metastatic cervical nodes for patients with head and neck squamous cell cancer
2012
The aim of this work was to determine whether classification of benign and metastatic cervical nodes based on diffusion weighted imaging (DWI) could be improved by use of a maximum likelihood algorithm for derivation of ADC parameters. A non linear least squares (LSQ) algorithm is usually used to fit parameters to the measured MR signal intensities as a function of b-value. LSQ assumes that the noise in high b-values is normally distributed whereas in reality it follows a Rice distribution. To account for the Rician noise, maximum likelihood (ML) algorithms have been proposed that provide unbiased ADC estimates. In this work the monoexponential, stretched exponential and biexponential model…
Acoustic and optical variations during rapid downward motion episodes in the deep north-western Mediterranean Sea
2011
An Acoustic Doppler Current Profiler (ADCP) was moored at the deep-sea site of the ANTARES neutrino telescope near Toulon, France, thus providing a unique opportunity to compare high-resolution acoustic and optical observations between 70 and 170 m above the sea bed at 2475 m. The ADCP measured downward vertical currents of magnitudes up to 0.03 m s-1 in late winter and early spring 2006. In the same period, observations were made of enhanced levels of acoustic reflection, interpreted as suspended particles including zooplankton, by a factor of about 10 and of horizontal currents reaching 0.35 m s-1. These observations coincided with high light levels detected by the telescope, interpreted …
A New Front-End High-Resolution Sampling Board for the New-Generation Electronics of EXOGAM2 and NEDA Detectors
2015
19th Real Time Conference (RT) -- MAY 26-30, 2014 -- Nara, JAPAN WOS: 000356458000028 This paper presents the final design and results of the FADC Mezzanine for the EXOGAM (EXOtic GAMma array spectrometer) and NEDA (Neutron Detector Array) detectors. The measurements performed include those of studying the effective number of bits, the energy resolution using HP-Ge detectors, as well as timing histograms and discrimination performance. Finally, the conclusion shows how a common digitizing device has been integrated in the experimental environment of two very different detectors which combine both low-noise acquisition and fast sampling rates. Not only the integration fulfilled the expected …
Pulse shape analysis of liquid scintillators for neutron studies
2002
The acquisition of signals from liquid scintillators with Flash ADC of high sampling rate ð 1G S=sÞ has been investigated. The possibility to record the signal waveform is of great advantage in studies with g’s and neutrons in a high count-rate environment, as it allows to easily identify and separate pile-up events. The shapes of pulses produced by g-rays and neutrons have been studied for two different liquid scintillators, NE213 and C6D6: A 1-parameter fitting procedure is proposed, which allows to extract information on the particle type and energy. The performance of this method in terms of energy resolution and n=g discrimination is analyzed, together with the capability to identify a…