Novel active function blocks and their applications in frequency filters and quadrature oscillators

Kmitočtové filtry a sinusoidní oscilátory jsou lineární elektronické obvody, které jsou používány v široké oblasti elektroniky a jsou základními stavebními bloky v analogovém zpracování signálu. V poslední dekádě pro tento účel bylo prezentováno velké množství stavebních funkčních bloků. V letech 2000 a 2006 na Ústavu telekomunikací, VUT v Brně byly definovány univerzální proudový konvejor (UCC) a univerzální napět'ový konvejor (UVC) a vyrobeny ve spolupráci s firmou AMI Semiconductor Czech, Ltd. Ovšem, stále existuje požadavek na vývoj nových aktivních prvků, které nabízejí nové výhody. Hlavní přínos práce proto spočívá v definici dalších původních aktivních stavebních bloků jako jsou differential-input buffered and transconductance amplifier (DBTA), current follower transconductance amplifier (CFTA), z-copy current-controlled current inverting transconductance amplifier (ZC-CCCITA), generalized current follower differential input transconductance amplifier (GCFDITA), voltage gain-controlled modified current-feedback operational amplifier (VGC-MCFOA), a minus-type current-controlled third-generation voltage conveyor (CC-VCIII-). Pomocí navržených aktivních stavebních bloků byly prezentovány původní zapojení fázovacích článků prvního řádu, univerzální filtry druhého řádu, ekvivalenty obvodu typu KHN, inverzní filtry, aktivní simulátory uzemněného induktoru a kvadraturní sinusoidní oscilátory pracující v proudovém, napět'ovém a smíšeném módu. Chování navržených obvodů byla ověřena simulací v prostředí SPICE a ve vybraných případech experimentálním měřením.Frequency filters and sinusoidal oscillators are linear electric circuits that are used in wide area of electronics and also are the basic building blocks in analogue signal processing. In the last decade, huge number of active building blocks (ABBs) were presented for this purpose. In 2000 and 2006, the universal current conveyor (UCC) and the universal voltage conveyor (UVC), respectively, were designed at the Department of Telecommunication, BUT, Brno, and produced in cooperation with AMI Semiconductor Czech, Ltd. There is still the need to develop new active elements that offer new advantages. The main contribution of this thesis is, therefore, the definition of other novel ABBs such as the differential-input buffered and transconductance amplifier (DBTA), the current follower transconductance amplifier (CFTA), the z-copy current-controlled current inverting transconductance amplifier (ZC-CCCITA), the generalized current follower differential input transconductance amplifier (GCFDITA), the voltage gain-controlled modified current-feedback operational amplifier (VGC-MCFOA), and the minus-type current-controlled third-generation voltage conveyor (CC-VCIII-). Using the proposed ABBs, novel structures of first-order all-pass filters, second-order universal filters, KHN-equivalent circuits, inverse filters, active grounded inductance simulators, and quadrature sinusoidal oscillators working in the current-, voltage-, or mixed-mode are presented. The behavior of the proposed circuits has been verified by SPICE simulations and in selected cases also by experimental measurements.

Electronic circuits and systems: A compilation

Technological information is presented electronic circuits and systems which have potential utility outside the aerospace community. Topics discussed include circuit components such as filters, converters, and integrators, circuits designed for use with specific equipment or systems, and circuits designed primarily for use with optical equipment or displays

Electronically Tunable Current-Mode Third-Order Square-Root-Domain Filter Design

In this study, electronically-tunable, current-mode, square-root-domain, third-order low-pass filter is proposed. The study is carried out with three circuit designs. First circuit is third-order low-pass Butterworth filter, second circuit is third-order low-pass Chebyshev filter and the last circuit is third-order low-pass elliptic filter. All the input and output values of the filter circuit are current. Only grounded capacitors and MOSFETs are required in order to realize the filter circuit. Additionally, natural frequency f0 of the current-mode filter can be adjusted electronically using outer current sources. To validate the theory and to demonstrate the performance of third-order filter, frequency and time domain simulations of PSPICE program are used. To that end, TSMC 0.35μm Level 3 CMOS process parameters are utilized to realize the simulations of the filter. © 2018 World Scientific Publishing Company

Realization of Resistorless Lossless Positive and Negative Grounded Inductor Simulators Using Single ZC-CCCITA

This paper is in continuation with the very recent work of Prasad et al. [14], wherein new realizations of grounded and floating positive inductor simulator using current differencing transconductance amplifier (CDTA) are reported. The focus of the paper is to provide alternate realizations of lossless, both positive and negative inductor simulators (PIS and NIS) in grounded form using z-copy current-controlled current inverting transconductance amplifier (ZC-CCCITA), which can be considered as a derivative of CDTA, wherein the current differencing unit (CDU) is reduced to a current-controlled current inverting unit. We demonstrate that only a single ZC-CCCITA and one grounded capacitor are sufficient to realize grounded lossless PIS or NIS. The proposed circuits are resistorless whose parameters can be controlled through the bias currents. The workability of the proposed PIS is validated by SPICE simulations on three RLC prototypes

An independent controller for active diesel exhaust aftertreatment.

An independent controller was proposed to perform real-time diagnosis and modeling based control for diesel aftertreatment devices, such as the diesel particulate filters (DPF) and the lean NOx traps (LNT). The diesel aftertreatment devices for this research were in active flow control configuration. As opposed to passive aftertreatment control where the engine tailors the raw exhaust conditions, in active aftertreatment configuration, the raw exhaust conditions were modified with independent controls, such as aftertreatment temperature control, exhaust flow control, and aftertreatment excess air/fuel ratio (A) control. The determination of the diesel engine transient exhaust gas temperature is essential for effective active flow aftertreatment control schemes. To overcome the slow response of the high-inertia thermocouples used in the harsh diesel exhaust environment, a temperature response model was developed as part of this research. The temperature response model was verified by tests conducted on a Yanmar NFD170 single cylinder diesel engine setup. The model was then implemented into a National Instrument PCI-6023E multifunction data acquisition board with LabVIEW. The LabVIEW program was tested on the Yanmar engine setup and was capable of estimating the transient exhaust gas temperature in real-time using the temperature data obtained from two high-inertia thermocouples with a proper diameter ratio. The simplified transient aftertreatment model representing the regeneration behavior of the DPF and the performance of the LNT were also proposed. (Abstract shortened by UMI.) Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2005 .W88. Source: Masters Abstracts International, Volume: 44-03, page: 1499. Thesis (M.A.Sc.)--University of Windsor (Canada), 2005

Characterisation of an Electrolyte-Gated Organic Field-Effect Transistor for the Measurement of Extracellular Potentials

Treballs Finals de Grau d'Enginyeria Biomèdica. Facultat de Medicina i Ciències de la Salut. Universitat de Barcelona. Curs: 2021-2022. Tutor/Director: Gabriel Gomila Lluch i Shubham Tanwa

Optical properties monitor: Experiment definition phase

The stability of materials used in the space environment will continue to be a limiting technology for space missions. The Optical Properties Monitor (OPM) Experiment provides a comprehensive space research program to study the effects of the space environment-both natural and induced-on optical, thermal and space power materials. The OPM Experiment was selected for definition under the NASA/OAST In-Space Technology Experiment Program. The results of the OPM Definition Phase are presented. The OPM Experiment will expose selected materials to the space environment and measure the effects with in-space optical measurements. In-space measurements include total hemispherical reflectance total integrated scatter and VUV reflectance/transmittance. The in-space measurements will be augmented with extensive pre- and post-flight sample measurements to determine other optical, mechanical, electrical, chemical or surface effects of space exposure. Environmental monitors will provide the amount and time history of the sample exposure to solar irradiation, atomic oxygen and molecular contamination

Design and implementation of a microgrid-capable solar inverter

Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2013.Cataloged from PDF version of thesis.Includes bibliographical references (page 31).The notion of a practical microgrid -- a small, interconnected system of generators and loads that operates both synchronously with a larger, centralized grid and isolated from the grid, autonomously -- has grown popular as electric utilities are installed more frequently in areas lacking a pre-existing central grid. To research the effects of both intentional disconnects and unintentional faults within a microgrid and between it and the central utility, we have constructed such a system in simulation by using hardware to simulate the real-world generators and loads of the microgrid and have connected it to the MIT utility.[1] The microgrid requires a clean, efficient switching system in order to connect and disconnect its components, and this thesis begins with an explanation of the control hardware and software interface implemented to do so. Next, this thesis details the design of one of the main generating sources for the microgrid, the inverter for a hardware-simulated solar panel. Solar panels with DC output are virtually always connected through a power inverter to produce the usable three-phase AC on the power grid. This particular inverter design is intended to be control-scheme agnostic; the actual operation of it will vary with different control algorithms. It is designed to be a general purpose, three phase 2.3 kW power inverter, albeit with specifically added modules to suit this particular microgrid. This thesis covers both the design of the circuit and the finished layout of its printed circuit board.by Gavin M. Darcey.M. Eng

Realization of Integrable Low- Voltage Companding Filters for Portable System Applications

Undoubtedly, today’s integrated electronic systems owe their remarkable performance primarily to the rapid advancements of digital technology since 1970s. The various important advantages of digital circuits are: its abstraction from the physical details of the actual circuit implementation, its comparative insensitiveness to variations in the manufacturing process, and the operating conditions besides allowing functional complexity that would not be possible using analog technology. As a result, digital circuits usually offer a more robust behaviour than their analog counterparts, though often with area, power and speed drawbacks. Due to these and other benefits, analog functionality has increasingly been replaced by digital implementations. In spite of the advantages discussed above, analog components are far from obsolete and continue to be key components of modern electronic systems. There is a definite trend toward persistent and ubiquitous use of analog electronic circuits in day-to-day life. Portable electronic gadgets, wireless communications and the widespread application of RF tags are just a few examples of contemporary developments. While all of these electronic systems are based on digital circuitry, they heavily rely on analog components as interfaces to the real world. In fact, many modern designs combine powerful digital systems and complementary analog components on a single chip for cost and reliability reasons. Unfortunately, the design of such systems-on-chip (SOC) suffers from the vastly different design styles of analog and digital components. While mature synthesis tools are readily available for digital designs, there is hardly any such support for analog designers apart from wellestablished PSPICE-like circuit simulators. Consequently, though the analog part usually occupies only a small fraction of the entire die area of an SOC, but its design often constitutes a major bottleneck within the entire development process. Integrated continuous-time active filters are the class of continuous-time or analog circuits which are used in various applications like channel selection in radios, anti-aliasing before sampling, and hearing aids etc. One of the figures of merit of a filter is the dynamic range; this is the ratio of the largest to the smallest signal that can be applied at the input of the filter while maintaining certain specified performance. The dynamic range required in the filter varies with the application and is decided by the variation in strength of the desired signal as well as that of unwanted signals that are to be rejected by the filter. It is well known that the power dissipation and the capacitor area of an integrated active filter increases in proportion to its dynamic range. This situation is incompatible with the needs of integrated systems, especially battery operated ones. In addition to this fundamental dependence of power dissipation on dynamic range, the design of integrated active filters is further complicated by the reduction of supply voltage of integrated circuits imposed by the scaling down of technologies to attain twin objective of higher speed and lower power consumption in digital circuits. The reduction in power consumption with decreasing supply voltage does not apply to analog circuits. In fact, considerable innovation is required with a reduced supply voltage even to avoid increasing power consumption for a given signal to noise ratio (S/N). These aspects pose a great hurdle to the active filter designer. A technique which has attracted the attention of circuit designers as a possible route to filters with higher dynamic range per unit power consumption is “companding”. Companding (compression-expansion) filters are a very promising subclass of continuous-time analog filters, where the input (linear) signal is initially compressed before it will be handled by the core (non-linear) system. In order to preserve the linear operation of the whole system, the non-linear signal produced by the core system is converted back to a linear output signal by employing an appropriate output stage. The required compression and expansion operations are performed by employing bipolar transistors in active region or MOS transistors in weak inversion; the systems thus derived are known as logarithmic-domain (logdomain) systems. In case MOS transistors operated in saturation region are employed, the derived structures are known as Square-root domain systems. Finally, the third class of companding filters can also be obtained by employing bipolar transistors in active region or MOS transistors in weak inversion; the derived systems are known as Sinh-domain systems. During the last several years, a significant research effort has been already carried out in the area of companding circuits. This is due to the fact that their main advantages are the capability for operation in low-voltage environment and large dynamic range originated from their companding nature, electronic tunability of the frequency characteristics, absence of resistors and the potential for operations in varied frequency regions.Thus, it is obvious that companding filters can be employed for implementing high-performance analog signal processing in diverse frequency ranges. For example, companding filters could be used for realizing subsystems in: xDSL modems, disk drive read channels, biomedical electronics, Bluetooth/ZigBee applications, phaselocked loops, FM stereo demodulator, touch-tone telephone tone decoder and crossover network used in a three-way high-fidelity loudspeaker etc. A number of design methods for companding filters and their building blocks have been introduced in the literature. Most of the proposed filter structures operate either above 1.5V or under symmetrical (1.5V) power supplies. According to data that provides information about the near future of semiconductor technology, International Technology Roadmap for Semiconductors (ITRS), in 2013, the supply voltage of digital circuits in 32 nm technology will be 0.5 V. Therefore, the trend for the implementation of analog integrated circuits is the usage of low-voltage building blocks that use a single 0.5-1.5V power supply. Therefore, the present investigation was primarily concerned with the study and design of low voltage and low power Companding filters. The work includes the study about: the building blocks required in implementing low voltage and low power Companding filters; the techniques used to realize low voltage and low power Companding filters and their various areas of application. Various novel low voltage and low power Companding filter designs have been developed and studied for their characteristics to be applied in a particular portable area of application. The developed designs include the N-th order universal Companding filter designs, which have been reported first time in the open literature. Further, an endeavor has been made to design Companding filters with orthogonal tuning of performance parameters so that the designs can be simultaneously used for various features. The salient features of each of the developed circuit are described. Electronic tunability is one of the major features of all of the designs. Use of grounded capacitors and resistorless designs in all the cases makes the designs suitable for IC technology. All the designs operate in a low-voltage and low-power environment essential for portable system applications. Unless specified otherwise, all the investigations on these designs are based on the PSPICE simulations using model parameters of the NR100N bipolar transistors and BSIM 0.35μm/TSMC 0.25μm /TSMC 0.18μm CMOS process MOS transistors. The performance of each circuit has been validated by comparing the characteristics obtained using simulation with the results present in the open literature. The proposed designs could not be realized in silicon due to non-availability of foundry facility at the place of study. An effort has already been started to realize some of the designs in silicon and check their applicability in practical circuits. At the basic level, one of the proposed Companding filter designs was implemented using the commercially available transistor array ICs (LM3046N) and was found to verify the theoretical predictions obtained from the simulation results