|
|
Pseudo-differential frequency filters operating in current mode
Velič, Ladislav ; Bečková, Zuzana (referee) ; Sládok, Ondřej (advisor)
This bachelor thesis deals with pseudo-differential frequency filters working in current mode. This thesis further describes different types of frequency filters and their characteristics. In the thesis there are described differencies between differential, non-differential and pseudo-differential filters and their schemes. The thesis then shows schemes of pseudo-differential filters working in current mode. Pseudo-differential band-pass filter is in practical part of the thesis constructed and its practical features are compared to the theoretical.
|
|
|
Synthesis of Modern Structures of Frequency Filters
Friedl, Martin ; Hájek, Karel (referee) ; Brančík, Lubomír (referee) ; Sedláček, Jiří (advisor)
Within modern frequency structures, the filter frequency region of up to 10 MHz constitutes a promising research topic that currently attracts intensive attention of specialists interested in the problem. The main reason of this fact consists in that the rapid development of modern technology allows the production of innovated structures of the analog frequency filters required in the defined band. In this context, however, it is also necessary to refine the methods applied in the synthesis and optimization of these structures; such improvement should be carried out with respect to fundamental properties and usability of today's active elements (operational amplifiers with voltage feedback whose Gain Bandwidth Product ranges within units of GHz, operational amplifiers with current feedback, conveyors, transimpedance operational amplifiers). In this thesis, active blocks of synthesis inductors (SIs) and frequency dependent negative resistors (FDNRs) are examined in detail, and the author provides novel formulas to define the basic parameters of the dual circuits. Due emphasis was placed on optimizing the basic building blocks of the second order and defining the variation of their properties caused by the addition of modern active elements. The blocks were analyzed and modified in view of their possible use in higher-order circuits. For active filters of a higher order, simulations were performed to indicate the actual sensitivity of the cascade and non-cascade ARC structures. The following phase of the research comprised mainly the designing of several filters, and this activity was further completed with the verification of the methodology for the synthesis and optimization of higher-order loss ladder filters with modern active blocks. Special attention was paid also to the methods enabling the optimization of such filters, which are invariably based on RLC prototypes. In order to verify the theoretical conclusions, the author materialized a large number of sample optimized filters and measured their parameters. The closing section of the thesis describes the use of the filters in specific applications.
|
|
|
Higher-order current mirror filters
Semmler, Petr ; Jeřábek, Jan (referee) ; Lattenberg, Ivo (advisor)
The bachelor's thesis deal with designing frequency filters fourth and sixth rule with current component CMI, GCMI and MCMI and with multi-output current mirrors. The introduction presents basic information about frequency filters divided base several views. Next information attention about current mirrors with divided base several views. Theory part is closed information about current component GCMI, CMI, MCMI. Second part my bachelor's thesis deal manual designing frequency filter with method of autonomous circuits. This method were designed several circuit for fourth and sixth rule. Then he was always one circuit selected for the final analysis, an analysis was performed using program PSpice and Snap. The last section is devoted to the replacement of components of current mirrors. It analyzed the functionality of current mirrors including verification of the functionality of filters incorporating current mirrors.
|
|
|
Active frequency filter using current mode
Paščinský, Jiří ; Dostál, Tomáš (referee) ; Slezák, Josef (advisor)
The aim of this work is design of frequency filter working in current mode. The introduction of the work deals with features and applications of frequency filters. Special attention is paid to the transfer function of the filter. In third chapter different operational modes of electrical circuits and their advantages and disadvantages are discussed. Attention is paid to active blocks suitable for circuits working in current mode. There is description of components AD844 and EL2082 which represent current conveyors of the second generation and are used in the designed filter. The last two chapters deal with design of component values of the frequency filter. The designed circuit was simulated in PSpice and the results were compared with measurments. Also sensitivity and tolerance analysis of the filter were performed.
|
|
|
Design of new active filters, using signal flow graphs
Jašek, František ; Kubánek, David (referee) ; Vrba, Kamil (advisor)
This master’s thesis describes the design of the frequency filters by the help of the graph of the signal flows. There are defined by modern components like GVC (Generalized Voltage Conveyor), GCC (Generalized Current Conveyor), CF (Current Follower), DO-CF (Dual-Output Current Follower), OTA (Operational Transconductance Amplifier), BOTA (Ballanced Operational Transconductance Amplifier) and CFTA (Current Follower Transconductance Amplifier), the graphs of the signal flows, which describe their activity in the thesis. In the other part of the thesis is illustrated the procedure of the design of the frequency filters by the help of the graphs of the signal flows. For the concrete design was selected in the first case as the active component double output current follower and in the second case the CFTA. There are noted all designed circuits of the frequency filters also their characteristic equations in this thesis. The activity of the selected circuits was remitted to the analysis in the simulation program called PSpice. Because the active components, with which was engaged in the design of the filter which doesn’t exist in the real form, that is why the UCC, which is sufficing for attestation of the function of the circuit, was used for the simulation. The simulation was implemented in the frequency range 10 Hz to 10 MHz.
|
|
|
Frequency filter
Suchánek, Tomáš ; Kubánek, David (referee) ; Káňa, Ladislav (advisor)
The main objective of this thesis is to design and implement integration that will be building block for tunable active filters 2nd range of low , high and band pass through the jet structure Sallen - Key. This work first examines the use of different types of frequency filters, the detailed design of the components and selection of a suitable operational amplifiers for participation. Practical part focuses on the production of the finished product, measure its parameters resulting in graphs.In implementing are used software such as simulation programme Micro-cap and layout editor Eagle.
|
|
|
Electronically controllable frequency filters with current active elements
Suchánek, Tomáš ; Lattenberg, Ivo (referee) ; Kubánek, David (advisor)
The aim of the thesis is to study the possibilities of the electronic frequency ?lter com- posed of active elements operating in current mode. The main opportunities lie in the change control parameters, most are marginal or quality factor frequency. As the active elements are considered especially CC (Current Convejor), controllable current ampli?er DACA (Digitally Adjustable Current Ampli?er) or combination with the current tracker MO-CF (Multiple Output Current Follower). Another part will focus on the management of the above parameters using digital potentiometers and choosing the appropriate ?lter structure. The ?nal task was to digital control parameters using a PC and measuring its properties.
|
|
|
Laboratory kit for demonstration of active low pass, high pass and band pass filter by Sallen-Key structure
Kadlec, Michal ; Smejkal, Vladimír (referee) ; Slezák, Josef (advisor)
The main aim of this work is to design electric circuit for realizing of low pass, high pass and band pass filter using Sallen – Key structure. It is active filter so this work pays attention to choose the suitable active element. I will analyze individual types of frequency filters, simulate designed structure and will choose suitable computing amplifier for our structure. I will simulate every circuit with ideal operational amplifier, with operational amplifier having real parameters and finally with our chosen operational amplifier. I will confront the difference of individual circuit, influence of real parameters of amplifier for the general process of resultant filter modul characteristics. I closer take a look at the output resistance influence of operational amplifier for the modul characteristics of choosen circuit (low pass filter). This project also includes the summary and analyses of individual possibilities of the electronic control applied to active filter parameters. The part of the project is also detailed analyze and process of realization of the final connection of laboratory instrument.
|
|
|
Design of a New Structure of an Active Filter on Transistor Level
Michalička, Filip ; Dvořák, Jan (referee) ; Bečková, Zuzana (advisor)
Bachelor's thesis deals with designs of new structures of active frequency filters which operate in voltage mode using active element designed on transistor level. The first part describes parameters and kinds of basic frequency filters and types of aproximation. The second part contains a briefing of unipolar transistors, MOS transistor and his properties. The next part deals with method of signal flow graphs and describes the topology of leap-frog frequency filters. Practical part shows transistor based design of an operational transconductance amplifier using transistors TSMC 0,18 µm from the Taiwan Semiconductor company and designs of two new structures of frequency filters using leap-frog topology. Last part presents schematic diagrams from simulation programms. Verification the function of the operational transconductance amplifier and analysis of the new filter structures is performed by simulation programms OrCAD Capture and PSPICE.
|
|
|
Pseudo-differential higher-order frequency filters
Jeleček, Jiří ; Dvořák, Jan (referee) ; Sládok, Ondřej (advisor)
This Master's thesis deals with pseudo-differential frequency higher order filters working in voltage mode. The thesis deals with the description of frequency filters, their types and applications. Follows an analysis of differential and pseudo-differential transmissions. Next part contains a description of used active elements (conveyors) at thesis (CCII, DVCC, DDCC, UCC). In the last part the thesis is devoted to the own design of the pseudo-differential filter. Design functionality is verified by experimental simulation.
|
guest ::
