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11	Měřicí modul s A/D převodníkem se současným vzorkováním / Measurement module with simultaneous-sampling A/D converter Křížek, Miroslav January 2009 (has links) In this work is designed programme unit for acquisition analog acoustic signlas from sensors. There is used accurate A/D converter ADS1287 by the company Texas Iinstrument with resolution of 24 bits to digitizing these signals. There is used 32-bit microprocessor AT91SAM7S64 by the company Atmel to control this A/D converter and sending digitized data to PC. This microprocessor has implemented USB interface. By force of developmental programme units whit microprocessor and A/D converter is produced programme for microprocessor in developmental setting IAR Embedded Workbench IDE 5.0 and simple aplication for PC in setting Borland C++ Builder. Both of those programs are in language C++. Rate of sampling is 26 kHz. On the basis is realized programme unit USB-ADC whit microprocessor and A/D converter.
12	Analýza diferenčních a nediferenčních filtračních struktur s řiditelným proudovým zesilovačem / Analysis of differential and non-differential filtering structures with adjustable current amplifier Dvořák, Jan January 2015 (has links) The master thesis deals with designs of the single-ended and the fully-differential secondorder frequency filters with adjustable parameters. This filters operate in the current mode where main element is the current amplifier DACA (Digitally Adjustable Current Amplifier). The first part describes basic behaviour of frequency filters and distribution according to filter funcion, used parts and structure. The second part of thesis describes the design of the frequency filters by the M-C signal-flow graphs and the transformating single-ended structures to the fully-differential forms. The next part deals with properties of the active elements and their simulation models. The following part describe six circuits of the frequency filters with adjustable parameters and their simulations. Four simulation models with different properties were used for simulating of the DACA in the each circuits. The last part deals with the practical design and measurement of the selected frequency filters.
13	Návrh plně diferenčních kmitočtových filtrů s proudovými aktivními prvky za pomoci metody grafu signálových toků / Fully-differential frequency filter designing with current active elements using signal-flow graphs method Štork, Petr January 2014 (has links) This master’s thesis deals with designing of fully-differential current-mode frequency filters using signal-flow graphs method. The first part is focused on a general description of frequency filters, its function and division. Active elements that create these frequency filters, such as multi-output current follower (MO-CF), balanced or multi-output transconductance amplifier (BOTA, MOTA) and digitally adjustace current amplifier (DACA) are described in the following part. Next, problems and various techniques of designing such filters are discussed on a theoretic basis. In the remaining part of the thesis there are six circuits of frequency filters described in detail; these connections are then transferred of passive elements to a proposed connections, with the assistance of a so-called reflection. Calculations of passive form are stated, as well as results of simulations, where nondifferential and differential variations of these designed frequency filters are compared. Finaly, it has been selected some variants of designs, which has been manufactured, then measured out and resulet has been compare between each other.
14	Diferenční kmitočtové filtry neceločíselného řádu / Fully-differential fractional frequency filters Zapletal, Miroslav January 2017 (has links) This diploma thesis is concentrated to fully differential and non-differential fractional-order filters with active elements. It describes how we can obtain fractional-order fully-differential filters design from non-differential design, thesis describes realization in OrCad program and simulation of this project. The first part of the thesis concerns theoretical analysis of frequency filters, active elements and fractional-order filters. The second part of the thesis includes designs of filters and simulations of differential structures and rest of non-differential structures simulation. The following part of the thesis concerns practical realization and experimental measurment of differential fractional-order filter. In the last part of this project, thesis evaluates all results which were revealed in our simulations and experimental measurment.
15	Chopping for over 50 MHz gain-bandwidth product current sense amplifiers achieving input noise level of 8.5 nV/√Hz Matthus, Christian D., Ellinger, Frank 22 May 2024 (has links) An accurate, high-speed, fully differential difference amplifier for current sensing utilizing the chopper approach was implemented in a 0.18 μm complementary metal-oxide-semiconductor (CMOS) technology. Unlike state-of-the-art solutions, we use a higher chopping frequency in the MHz range due to the bandwidth requirements of the introduced circuits for the latter application, namely, low-side phase-current measurement in motor control circuits. Except the low-pass filter (LPF) effect of the output stage, no additional LPF was integrated in hardware at the output of the circuits. We show that on the other hand a digital LPF, which can be integrated in the field-programmable gate-array (FPGA) logic or microcontroller used for the motor control, offers a higher flexibility in terms of filter design. Weak input signals of only few mV can be reconstructed with a high accuracy. This is demonstrated for a 500 kHz rectangular signal and a chopping frequency of 20 MHz. Note that an input-signal frequency of several hundreds of kHz with harmonics in the MHz region is very challenging for chopper amplifiers. Still, a significant decrease of the input-referred noise is demonstrated, especially cancelling out the 1/f-noise achieving a remaining noise floor of approximately 8.5 nV/√Hz. Overall, the input-referred noise level can be pushed far below 50 μV (root mean square). Moreover, using a quite relaxed second-order Butterworth filter with a 3 dB corner frequency of 1 MHz, input-referred noise levels of 10 μV (root mean square) can be easily achieved at the costs of reduced bandwidth. The lowest achieved input offset is 50 μV. The gain is adjusted by resistive feedback and is approximately 40 dB. Hence, the amplifier is suitable for current sensing in motor control circuits, and a significant reduction of the shunt resistance typically used for this purpose will be possible. info:eu-repo/classification/ddc/620 ddc:620
16	Design of a Low Power, High Performance Track-and-Hold Circuit in a 0.18µm CMOS Technology / Design av en lågeffekts högprestanda track-and-hold krets i en 0.18µm CMOS teknologi. Säll, Erik January 2002 (has links) This master thesis describes the design of a track-and-hold (T&H) circuit with 10bit resolution, 80MS/s and 30MHz bandwidth. It is designed in a 0.18µm CMOS process with a supply voltage of 1.8 Volt. The circuit is supposed to work together with a 10bit pipelined analog to digital converter. A switched capacitor topology is used for the T&H circuit and the amplifier is a folded cascode OTA with regulated cascode. The switches used are of transmission gate type. The thesis presents the design decisions, design phase and the theory needed to understand the design decisions and the considerations in the design phase. The results are based on circuit level SPICE simulations in Cadence with foundry provided BSIM3 transistor models. They show that the circuit has 10bit resolution and 7.6mW power consumption, for the worst-case frequency of 30MHz. The requirements on the dynamic performance are all fulfilled, most of them with large margins. Electronics track-and-hold CMOS 0.18 low power high performance 10-bit folded cascode switch theory correlated double sampling CDS fully differential gain boosting regulated cascode transmission gate transmission gate switch clock generator clock driver bias bias circuit amplifier design switch design common mode feedback CMFB 80MSPS 80MS/s Elektronik Electronics Elektronik
17	Design of a Low Power, High Performance Track-and-Hold Circuit in a 0.18µm CMOS Technology / Design av en lågeffekts högprestanda track-and-hold krets i en 0.18µm CMOS teknologi. Säll, Erik January 2002 (has links) <p>This master thesis describes the design of a track-and-hold (T&H) circuit with 10bit resolution, 80MS/s and 30MHz bandwidth. It is designed in a 0.18µm CMOS process with a supply voltage of 1.8 Volt. The circuit is supposed to work together with a 10bit pipelined analog to digital converter. </p><p>A switched capacitor topology is used for the T&H circuit and the amplifier is a folded cascode OTA with regulated cascode. The switches used are of transmission gate type. </p><p>The thesis presents the design decisions, design phase and the theory needed to understand the design decisions and the considerations in the design phase. </p><p>The results are based on circuit level SPICE simulations in Cadence with foundry provided BSIM3 transistor models. They show that the circuit has 10bit resolution and 7.6mW power consumption, for the worst-case frequency of 30MHz. The requirements on the dynamic performance are all fulfilled, most of them with large margins.</p> Electronics track-and-hold CMOS 0.18 low power high performance 10-bit folded cascode switch theory correlated double sampling CDS fully differential gain boosting regulated cascode transmission gate transmission gate switch clock generator clock driver bias bias circuit amplifier design switch design common mode feedback CMFB 80MSPS 80MS/s Elektronik Electronics Elektronik
18	Kmitočtové filtry s proudovými aktivními prvky / Frequency Filters with Current Active Elements Jeřábek, Jan January 2011 (has links) This doctoral thesis is focused mainly on research of new current active elements and their applications in frequency filters suitable for current-mode. Work is focused on design of new filtering structures suitable for traditional single-ended signal processing and also on structures suitable for fully-differential applications. The thesis contains three designed general conceptions of KHN-type second-order filters. Adjustability of quality factor and pole frequency is provided by controllable current amplifiers that are placed properly in designed structures. Structures also contain second-generation current conveyors, multiple-output current followers, transconductance amplifiers and their fully-differential equivalents. There are lot of possible solutions that could be obtained from general structures, some of them are presented in the work. The thesis also presents several multifunctional and also single-purpose filtering structures of second-order and two variants of n-th order synthetic elements which are suitable to realize higher order filters both in single ended and fully differential type. In each case, functionality of new solutions is verified by simulations and in several cases also by real measurement.
19	Diferenční a pseudodiferenční kmitočtové filtry / Differential and pseudo-differential frequency filters Sládok, Ondřej January 2016 (has links) This thesis deals with fully differential and pseudo-differential frequency filters. Significant emphasis is placed on the characteristics of common-mode signal. Further, the text deals with the design issue of fully-differential structure and transformation of non-differential to pseudo-differential structures. In the thesis one non-differential structure, one fully-differential and three pseudo-differential structures are proposed, one of them working in current mode. The thesis also describes the analysis from the perspective of non-ideal properties of the active element of two circuit solutions, which is trying to find the optimal solution. In each case, functionality of new solutions is verified by simulations and in several cases also by experimental measurement.
20	Plně diferenční kmitočtové filtry s moderními aktivními prvky / Fully-Differential Frequency Filters with Modern Active Elements Langhammer, Lukáš January 2016 (has links) Tato disertační práce se zaměřuje na výzkum v oblasti frekvenčních filtrů. Hlavním cílem je navrhnout a analyzovat plně diferenční kmitočtové filtry pracující v proudovém módu a využívající moderní aktivní prvky. Prezentované filtry jsou navrženy za použití proudových sledovačů, operačních transkonduktančních zesilovačů, plně diferenčních proudových zesilovačů a transrezistančních zesilovačů. Návrh se zaměřuje na možnost řídit některý z typických parametrů filtru pomocí řiditelných aktivních prvků, které jsou vhodně umístněny do obvodové struktury. Jednotlivé prezentované filtry jsou navrženy v nediferenční a diferenční verzi. Velký důraz je věnován srovnání plně diferenčních struktur s jejich odpovídajícími nediferenčními formami. Funkčnost jednotlivých návrhů je ověřena simulacemi a v některých případech i experimentálním měřením.

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