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Design and analysis of electronically reconfigurable filtering structures
Kříčka, Tomáš ; Dvořák, Jan (referee) ; Langhammer, Lukáš (advisor)
This bachelor thesis deals with the proposal of analog filters with the ability of the electronic reconfiguration. The main aim was to propose three fully electronically reconfigurable filters using different methods. The work focuses on the use of modern active elements that ensure the electronic reconfiguration. Specifically on operational transconductivity amplifiers, second-generation current conveyors and current amplifiers. The transfer functions are simulated in the Orcad PSpice software, at the ideal and behavioral level. Sensitivity and parasitic analysis is applied to the two proposed filtration structures. Both structures are made on printed circuit boards, which are measured and then their transfer functions are compared with the simulated functions.
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Synthesis of the electronically reconfigurable frequency filters
Michalička, Filip ; Dvořák, Jan (referee) ; Langhammer, Lukáš (advisor)
This diploma thesis deals with design of reconection-less electronically reconfigurable filter structures which have single input and single output using unconventional active elements, which have ability to adjust one of their parameter e.g. gain or transconductance. The first part describes basic parameters of frequency filters, the division of filters by frequency transfer response and used circuit elements, their operational modes, the principle of reconnection-less electronically reconfiguration and the circuit design method MUNV. Second part describes all active elements used in the proposal of filters, their properties and the implementation using existing transistor-level models. The third part contains the design of three reconnection-less electronically reconfigurable filters and the simulations results obtained from simulation programs OrCAD Capture and PSpice. The obtained results were compared with theoretical behaviour. This part also contains results of these analyses: sensitivity, parasitic, Monte Carlo and temperature to determine the behaviour in varied cases.
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Fully-Differential Frequency Filters with Modern Active Elements
Langhammer, Lukáš ; Dostál, Tomáš (referee) ; Štork, Milan (referee) ; Jeřábek, Jan (advisor)
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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Electronically tunable oscillators
Polanský, David ; Šotner, Roman (referee) ; Petržela, Jiří (advisor)
The goal of bacheolor’s project introduce the reader to the basic principles of oscillator with a possibility of coherent electrical tunning frequency. Project is focused on utilization of non-standard active elements like OTA and CCII. A few wiring circuits are listed, in which it's tunning scale is calculated in PSpise program. Next these devices are compared.
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Nonlinear circuits using current active elements
Langhammer, Lukáš ; Kubánek, David (referee) ; Koton, Jaroslav (advisor)
This thesis deals with non-linear curcuit structures with current active elements. In its introduction this work deals with a description of the current active elements, such as current conveyor, transconductance operational amplifier and current follower. Further the text pays attention to the possiblities of the circuits for modification signals in analogue technology. First are described circuits of diode limiters and transducer. Great attention is paid to the amplifiers with current active elements. Are propřed simulated and practically realized circuits of universal precise full-wave rectifiers using operational amplifier and current conveyor and made comparisons of known and proposed circuits. The paper also discussed other circuit structures using of current active elements, such as multiplier, divider, a triangular signal generator and oscillators.
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Oscillators RC for higher frequency range
Polách, Petr ; Petržela, Jiří (referee) ; Dostál, Tomáš (advisor)
This thesis deals with RC oscillators applicable in higher frequency ranges with the use of modern active elements. For individual function blocks (conveyor, current feedback amplifier, operational transconductance amplifier, voltage feedback amplifier) suitable models are suggested for the circuit simulator PSpice covering their characteristics on various levels, from an ideal one up to the full description of parasitic effects. On the basis of the study of recommended literature and company documentation various oscillator connections of the ranks 2 and 3 are suggested. By analysis through computer (PSpice, SNAP) the fulfilment of oscillation conditions, onset of oscillations were verified and by means of suitable simulations the effects of the impact on the parasitic characteristics of active elements was examined. Finally there are two oscillator connections stated and verified by simulations with the possibility of electronic retuning.
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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.
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Electronically Configurable Transfer Structures
Langhammer, Lukáš ; Hospodka, Jiří (referee) ; Vávra, Jiří (referee) ; Šotner, Roman (advisor)
Práce se zaměřuje na vývoj a výzkum v oblasti elektronicky rekonfigurovatelných přenosových struktur. Primárním cílem je návrh těchto struktur za užití moderních elektronicky řiditelných aktivních prvků. V práci je prezentováno množství elektronicky rekonfigurovatelných filtračních struktur, jež byly vytvořeny za užití různých návrhových metod. Důraz je dále kladen na možnost řídit některý z typických parametrů filtru pomocí řiditelných aktivních prvků. Práce dále obsahuje několik obvodových návrhů aktivních prvků či stavebních bloků s vhodně řešenou elektronickou řiditelností, tak, aby tyto prvky/bloky mohly být dále použity pro návrh elektronicky rekonfigurovatelných filtrů. Správnost návrhu jednotlivých zapojení je podpořena PSpice a Cadence simulacemi s modely na tranzistorové úrovni. Vybraná zapojení jsou dále realizována za pomocí dostupných aktivních prvků a podrobena experimentálnímu měření.
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