Low Voltage Low Power Analogue Circuits Design

Disertační práce je zaměřena na výzkum nejběžnějších metod, které se využívají při návrhu analogových obvodů s využití nízkonapěťových (LV) a nízkopříkonových (LP) struktur. Tyto LV LP obvody mohou být vytvořeny díky vyspělým technologiím nebo také využitím pokročilých technik návrhu. Disertační práce se zabývá právě pokročilými technikami návrhu, především pak nekonvenčními. Mezi tyto techniky patří využití prvků s řízeným substrátem (bulk-driven - BD), s plovoucím hradlem (floating-gate - FG), s kvazi plovoucím hradlem (quasi-floating-gate - QFG), s řízeným substrátem s plovoucím hradlem (bulk-driven floating-gate - BD-FG) a s řízeným substrátem s kvazi plovoucím hradlem (quasi-floating-gate - BD-QFG). Práce je také orientována na možné způsoby implementace známých a moderních aktivních prvků pracujících v napěťovém, proudovém nebo mix-módu. Mezi tyto prvky lze začlenit zesilovače typu OTA (operational transconductance amplifier), CCII (second generation current conveyor), FB-CCII (fully-differential second generation current conveyor), FB-DDA (fully-balanced differential difference amplifier), VDTA (voltage differencing transconductance amplifier), CC-CDBA (current-controlled current differencing buffered amplifier) a CFOA (current feedback operational amplifier). Za účelem potvrzení funkčnosti a chování výše zmíněných struktur a prvků byly vytvořeny příklady aplikací, které simulují usměrňovací a induktanční vlastnosti diody, dále pak filtry dolní propusti, pásmové propusti a také univerzální filtry. Všechny aktivní prvky a příklady aplikací byly ověřeny pomocí PSpice simulací s využitím parametrů technologie 0,18 m TSMC CMOS. Pro ilustraci přesného a účinného chování struktur je v disertační práci zahrnuto velké množství simulačních výsledků.The dissertation thesis is aiming at examining the most common methods adopted by analog circuits' designers in order to achieve low voltage (LV) low power (LP) configurations. The capability of LV LP operation could be achieved either by developed technologies or by design techniques. The thesis is concentrating upon design techniques, especially the non–conventional ones which are bulk–driven (BD), floating–gate (FG), quasi–floating–gate (QFG), bulk–driven floating–gate (BD–FG) and bulk–driven quasi–floating–gate (BD–QFG) techniques. The thesis also looks at ways of implementing structures of well–known and modern active elements operating in voltage–, current–, and mixed–mode such as operational transconductance amplifier (OTA), second generation current conveyor (CCII), fully–differential second generation current conveyor (FB–CCII), fully–balanced differential difference amplifier (FB–DDA), voltage differencing transconductance amplifier (VDTA), current–controlled current differencing buffered amplifier (CC–CDBA) and current feedback operational amplifier (CFOA). In order to confirm the functionality and behavior of these configurations and elements, they have been utilized in application examples such as diode–less rectifier and inductance simulations, as well as low–pass, band–pass and universal filters. All active elements and application examples have been verified by PSpice simulator using the 0.18 m TSMC CMOS parameters. Sufficient numbers of simulated plots are included in this thesis to illustrate the precise and strong behavior of structures.

Unconventional Circuit Elements for Ladder Filter Design

Kmitočtové filtry jsou lineární elektrické obvody, které jsou využívány v různých oblastech elektroniky. Současně tvoří základní stavební bloky pro analogové zpracování signálů. V poslední dekádě bylo zavedeno množství aktivních stavebních bloků pro analogové zpracování signálů. Stále však existuje potřeba vývoje nových aktivních součástek, které by poskytovaly nové možnosti a lepší parametry. V práci jsou diskutovány různé aspekty obvodů pracujících v napěťovém, proudovém a smíšném módu. Práce reaguje na dnešní potřebu nízkovýkonových a nízkonapěťových aplikací pro přenosné přístroje a mobilní komunikační systémy a na problémy jejich návrhu. Potřeba těchto výkonných nízkonapěťových zařízení je výzvou návrhářů k hledání nových obvodových topologií a nových nízkonapěťových technik. V práci je popsána řada aktivních prvků, jako například operační transkonduktanční zesilovač (OTA), proudový konvejor II. generace (CCII) a CDTA (Current Differencing Transconductance Amplifier). Dále jsou navrženy nové prvky, jako jsou VDTA (Voltage Differencing Transconductance Amplifier) a VDVTA (Voltage Differencing Voltage Transconductance Amplifier). Všechny tyto prvky byly rovněž implementovány pomocí "bulk-driven" techniky CMOS s cílem realizace nízkonapěťových aplikací. Tato práce je rovněž zaměřena na náhrady klasických induktorů syntetickými induktory v pasivních LC příčkových filtrech. Tyto náhrady pak mohou vést k syntéze aktivních filtrů se zajímavými vlastnostmi.Frequency filters are linear electric circuits that are used in wide area of electronics. They are also the basic building blocks in analogue signal processing. In the last decade, a huge number of active building blocks for analogue signal processing was introduced. However, there is still the need to develop new active elements that offer new possibilities and better parameters. The current-, voltage-, or mixed-mode analog circuits and their various aspects are discussed in the thesis. This work reflects the trend of low-power (LP) low-voltage (LV) circuits for portable electronic and mobile communication systems and the problems of their design. The need for high-performance LV circuits encourages the analog designers to look for new circuit architectures and new LV techniques. This thesis presents various active elements such as Operational Transconductance Amplifier (OTA), Current Conveyor of Second Generation (CCII), and Current Differencing Transconductance Amplifier (CDTA), and introduces novel ones, such as Voltage Differencing Transconductance Amplifier (VDTA) and Voltage Differencing Voltage Transconductance Amplifier (VDVTA). All the above active elements were also designed in CMOS bulk-driven technology for LP LV applications. This thesis is also focused on replacement of conventional inductors by synthetic ones in passive LC ladder filters. These replacements can lead to the synthesis of active filters with interesting parameters.

Analog baseband circuits for WCDMA direct-conversion receivers

This thesis describes the design and implementation of analog baseband circuits for low-power single-chip WCDMA direct-conversion receivers. The reference radio system throughout the thesis is UTRA/FDD. The analog baseband circuit consists of two similar channels, which contain analog channel-select filters, programmable-gain amplifiers, and circuits that remove DC offsets. The direct-conversion architecture is described and the UTRA/FDD system characteristics are summarized. The UTRA/FDD specifications define the performance requirement for the whole receiver. Therefore, the specifications for the analog baseband circuit are obtained from the receiver requirements through calculations performed by hand. When the power dissipation of an UTRA/FDD direct-conversion receiver is minimized, the design parameters of an all-pole analog channel-select filter and the following Nyquist rate analog-to-digital converter must be considered simultaneously. In this thesis, it is shown that minimum power consumption is achieved with a fifth-order lowpass filter and a 15.36-MS/s Nyquist rate converter that has a 7- or 8-bit resolution. A fifth-order Chebyshev prototype with a passband ripple of 0.01 dB and a −3-dB frequency of 1.92-MHz is adopted in this thesis. The error-vector-magnitude can be significantly reduced by using a first-order 1.4-MHz allpass filter. The selected filter prototype fulfills all selectivity requirements in the analog domain. In this thesis, all the filter implementations use the opamp-RC technique to achieve insensitivity to parasitic capacitances and a high dynamic range. The adopted technique is analyzed in detail. The effect of the finite opamp unity-gain bandwidth on the filter frequency response can be compensated for by using passive methods. Compensation schemes that also track the process and temperature variations have been developed. The opamp-RC technique enables the implementation of low-voltage filters. The design and simulation results of a 1.5-V 2-MHz lowpass filter are discussed. The developed biasing scheme does not use any additional current to achieve the low-voltage operation, unlike the filter topology published previously elsewhere. Methods for removing DC offsets in UTRA/FDD direct-conversion receivers are presented. The minimum areas for cascaded AC couplings and DC-feedback loops are calculated. The distortion of the frequency response of a lowpass filter caused by a DC-feedback loop connected over the filter is calculated and a method for compensating for the distortion is developed. The time constant of an AC coupling can be increased using time-constant multipliers. This enables the implementation of AC couplings with a small silicon area. Novel time-constant multipliers suitable for systems that have a continuous reception, such as UTRA/FDD, are presented. The proposed time-constant multipliers only require one additional amplifier. In an UTRA/FDD direct-conversion receiver, the reception is continuous. In a low-power receiver, the programmable baseband gain must be changed during reception. This may produce large, slowly decaying transients that degrade the receiver performance. The thesis shows that AC-coupling networks and DC-feedback loops can be used to implement programmable-gain amplifiers, which do not produce significant transients when the gain is altered. The principles of operation, the design, and the practical implementation issues of these amplifiers are discussed. New PGA topologies suitable for continuously receiving systems have been developed. The behavior of these circuits in the presence of strong out-of-channel signals is analyzed. The interface between the downconversion mixers and the analog baseband circuit is discussed. The effect of the interface on the receiver noise figure and the trimming of mixer IIP2 are analyzed. The design and implementation of analog baseband circuits and channel-select filters for UTRA/FDD direct-conversion receivers are discussed in five application cases. The first case presents the analog baseband circuit for a chip-set receiver. A channel-select filter that has an improved dynamic range with a smaller supply current is presented next. The third and fifth application cases describe embedded analog baseband circuits for single-chip receivers. In the fifth case, the dual-mode analog baseband circuit of a quad-mode receiver designed for GSM900, DCS1800, PCS1900, and UTRA/FDD cellular systems is described. A new, highly linear low-power transconductor is presented in the fourth application case. The fourth application case also describes a channel-select filter. The filter achieves +99-dBV out-of-channel IIP2, +45-dBV out-of-channel IIP3 and 23-μVRMS input-referred noise with 2.6-mA current from a 2.7-V supply. In the fifth application case, a corresponding performance is achieved in UTRA/FDD mode. The out-of-channel IIP2 values of approximately +100 dBV achieved in this work are the best reported so far. This is also the case with the figure of merits for the analog channel-select filter and analog baseband circuit described in the fourth and fifth application cases, respectively. For equal power dissipation, bandwidth, and filter order, these circuits achieve approximately 10 dB and 15 dB higher spurious-free dynamic ranges, respectively, when compared to implementations that are published elsewhere and have the second best figure of merits.reviewe

Electronics for Sensors

The aim of this Special Issue is to explore new advanced solutions in electronic systems and interfaces to be employed in sensors, describing best practices, implementations, and applications. The selected papers in particular concern photomultiplier tubes (PMTs) and silicon photomultipliers (SiPMs) interfaces and applications, techniques for monitoring radiation levels, electronics for biomedical applications, design and applications of time-to-digital converters, interfaces for image sensors, and general-purpose theory and topologies for electronic interfaces

Активные фильтры на тонкопленочных пьезоэлектрических резонаторах

Дисертація присвячена розробленню класу пристроїв частотної селекції сигналів на основі активних елементів і тонкоплівкових п’єзоелектричних резонаторів для діапазону частот 0,1..10 ГГц, що поєднують поліпшені електричні та експлуатаційні характеристики, а також можливість інтеграції за технологією ІС. Проведено дослідження ТПР методом скінченних елементів та розроблено широкосмугову модель резонатора, придатну для моделювання електричних характеристик конструкцій резонаторів мембранного типу та з бреггівським відбивачем. Розроблено модифіковану макромодель ОПС, у якій застосована секція нелінійного підсилення на основі поліномів Чебишева та включені нелінійні моделі теплового та флікер шумів. Проведено аналіз впливу реактивних навантажень з функцією перелаштування на характеристики ТПР. Наведено схеми активних імітаторів індуктивності та від’ємної ємності на основі ОПС. Показана можливість використання таких схем для реалізації ланок активних фільтрів з діапазоном перебудови до 200% та вище. Запропоновано метод перетворення імпедансу ТПР із використанням гіратора та показана практична можливість електронного перелаштування ефективної площі резонатора, що дозволяє зменшити габарити фільтрів. Розроблено алгоритм синтезу фільтрів, заснований на заміщенні прототипів пасивних LC фільтрів активними аналогами на ТПР, що забезпечують поліпшені характеристики за рахунок високої вихідної добротності і стабільності пасивної підсхеми. Приведені приклади застосування такого підходу для реалізації малогабаритних активних ФНЧ і ФВЧ на ТПР

Management and Services

Management in all business areas and organisational activities are the acts of getting people together to accomplish desired goals and objectives. Service is intangible, therefore, it is not too easy to define the theory application in varieties of service industries. Service Management usually incorporates automated systems along with skilled labour; it also provides service development. Due to enormous demand of service industries and management development, the book under the title "Management and Services" would create a milestone in management arena for all categories of readers including Business Administration, Engineering and Architecture. This book covers educational service development, service-oriented-architecture and case research analysis, including theory application in network security, GRID technology, integrated circuit application. The book is comprised of five chapters and has been divided into two parts. Part A contains chapters on service development in educational institutions and it depicts the application of supply chain management concept in service industries like tertiary educational institutions and multiple ways of web 2.0 applications transforming learning patterns and pathways. To understand the subject in a practical manner, Part B of this book consists of noteworthy case studies and research papers on management and services and represents theory application of Data mining, Fuzzy Cluster, Game theory, GRID Technology, simulation of Operational Amplifier and Current Controlled Conveyor II in network security, architecture, and integrated circuit application

BP filters using second-generation current conveyors with low sensitivity and low noise in integrated technology

U ovom radu je prikazan postupak projektiranja i analize pojasno-propusnog filtra četvrtog reda (PP4) aproksimacije po Chebyshevu. Filtar je izveden u integriranoj tehnologiji I3T80 (AMS 0,35 µm) koristeći strujne prijenosnike druge generacije. Za sve potrebne analize i simulacije tokom projektiranja filtra korišteni su "Pspice" i ''Cadence Virtuoso'' programski alati. Uloga električnih filtara je da odvoje pojedine frekvencije iz cjelokupnog spektra signala uz što manje izobličenje i šum. Analogni aktivni filtri u strujnom režimu rada su pogodni za visoke brzine rada, niski šum i nisku osjetljivosti na tolerancije pasivnih komponenata što ih čini primjenjivim za integriranje. Integriranjem ovakvih sklopova postižu se još bolja svojstva prilikom rada u realnim uvjetima zbog činjenice da se komponente mogu bolje upariti. Uz električnu izvedbu filtra napravljen je i layout koji omogućuje dodatne post-layout simulacije uzevši u obzir sve parazitne elemente koji se pojavljuju u realnoj izvedbi. Korištenje realnih strujnih prijenosnika (CCII) za izvedbu integratora s negativnom povratnom vezom u svrhu realizacije filtra neidealnosti CCII su se pokazale kao izvor problema. U ovom radu također su definirani uvjeti koje realni CCII treba zadovoljiti da bi filtar bio izvediv. Rezultati simulacija realnog rada sklopa pokazuju dobro poklapanje s teoretskim analizama što omogućuje stvarnu izvedbu sklopa u siliciju. Na kraju je pomoću Monte Carlo analize pokazano kako realizacija filtra s negativnom povratnom vezom ima manju osjetljivost na tolerancije pasivnih komponenata u području propuštanja. Realizacija s povratnom vezom također posjeduje reducirani termički šum na izlazu filtra.This paper describes design process and analysis of integrated fourth-order band-pass filter (BP4), approximated by Chebyshev. Filter is implemented in integrated technology I3T80 using second-generation current conveyors (CCII). For the purpose of all analysis during design process, Pspice and Cadence Virtuoso program tools were used. The role of electric filters is to separate individual frequencies from the entire spectrum of the signal with adding minimal noise and distortion. Analog active filters in the current mode are appropriate for high speed operation, low noise and low sensitivity on passive components tolerance, what makes them suitable for integrated designs. When integrated, these circuits can achieve even better performance while working in real conditions because components can be matched properly. Using non-ideal CMOS CCIIs for the integrators in the negative feedback loop of the biquads, the realization of high pole Q factors is a problem, because of the CCII nonidealities. In this paper we show under which conditions the circuits are realizable. Along with electrical design, layout of integrated circuit has been made in order to conduct post-layout simulations with real parameters and geometry of the system. Simulation results showed good match with theoretical expectations, what indicates that the circuit can be produced in silicon. Finally, it is shown using analysis with Monte Carlo runs that the sensitivity of the coupled band-pass filter is much lower in the pass-band region when compared to the classical cascaded realization. The coupled realization also possesses reduced thermal noise at the filter output

BP filters using second-generation current conveyors with low sensitivity and low noise in integrated technology

U ovom radu je prikazan postupak projektiranja i analize pojasno-propusnog filtra četvrtog reda (PP4) aproksimacije po Chebyshevu. Filtar je izveden u integriranoj tehnologiji I3T80 (AMS 0,35 µm) koristeći strujne prijenosnike druge generacije. Za sve potrebne analize i simulacije tokom projektiranja filtra korišteni su "Pspice" i ''Cadence Virtuoso'' programski alati. Uloga električnih filtara je da odvoje pojedine frekvencije iz cjelokupnog spektra signala uz što manje izobličenje i šum. Analogni aktivni filtri u strujnom režimu rada su pogodni za visoke brzine rada, niski šum i nisku osjetljivosti na tolerancije pasivnih komponenata što ih čini primjenjivim za integriranje. Integriranjem ovakvih sklopova postižu se još bolja svojstva prilikom rada u realnim uvjetima zbog činjenice da se komponente mogu bolje upariti. Uz električnu izvedbu filtra napravljen je i layout koji omogućuje dodatne post-layout simulacije uzevši u obzir sve parazitne elemente koji se pojavljuju u realnoj izvedbi. Korištenje realnih strujnih prijenosnika (CCII) za izvedbu integratora s negativnom povratnom vezom u svrhu realizacije filtra neidealnosti CCII su se pokazale kao izvor problema. U ovom radu također su definirani uvjeti koje realni CCII treba zadovoljiti da bi filtar bio izvediv. Rezultati simulacija realnog rada sklopa pokazuju dobro poklapanje s teoretskim analizama što omogućuje stvarnu izvedbu sklopa u siliciju. Na kraju je pomoću Monte Carlo analize pokazano kako realizacija filtra s negativnom povratnom vezom ima manju osjetljivost na tolerancije pasivnih komponenata u području propuštanja. Realizacija s povratnom vezom također posjeduje reducirani termički šum na izlazu filtra.This paper describes design process and analysis of integrated fourth-order band-pass filter (BP4), approximated by Chebyshev. Filter is implemented in integrated technology I3T80 using second-generation current conveyors (CCII). For the purpose of all analysis during design process, Pspice and Cadence Virtuoso program tools were used. The role of electric filters is to separate individual frequencies from the entire spectrum of the signal with adding minimal noise and distortion. Analog active filters in the current mode are appropriate for high speed operation, low noise and low sensitivity on passive components tolerance, what makes them suitable for integrated designs. When integrated, these circuits can achieve even better performance while working in real conditions because components can be matched properly. Using non-ideal CMOS CCIIs for the integrators in the negative feedback loop of the biquads, the realization of high pole Q factors is a problem, because of the CCII nonidealities. In this paper we show under which conditions the circuits are realizable. Along with electrical design, layout of integrated circuit has been made in order to conduct post-layout simulations with real parameters and geometry of the system. Simulation results showed good match with theoretical expectations, what indicates that the circuit can be produced in silicon. Finally, it is shown using analysis with Monte Carlo runs that the sensitivity of the coupled band-pass filter is much lower in the pass-band region when compared to the classical cascaded realization. The coupled realization also possesses reduced thermal noise at the filter output