Using bandgap engineering, silicon-germanium (SiGe) BiCMOS technology effectively combines III-V transistor performance with the cost and integration advantages associated with CMOS manufacturing. The suitability of SiGe technology for cryogenic and radiation-intense environments is well known, yet SiGe has been generally overlooked for applications involving extreme high temperature operation. This work is an investigation into the potential capabilities of SiGe technology for operation up to 300°C, including the development of packaging and testing procedures to enable the necessary measurements. At the device level, SiGe heterojunction bipolar transistors (HBTs), field-effect transistors (FETs), and resistors are verified to maintain acceptable functionality across the temperature range, laying the foundation for high temperature circuit design. This work also includes the characterization of existing bandgap references circuits, redesign for high temperature operation, validation, and further optimization recommendations. In addition, the performance of temperature sensor, operational amplifier, and output buffer circuits under extreme high temperature conditions is presented. To the author's knowledge, this work represents the first demonstration of functional circuits from a SiGe technology platform in ambient temperatures up to 300°C; furthermore, the optimized bandgap reference presented in this work is believed to show the best performance recorded across a 500°C range in a bulk-silicon technology platform.

The theme of the master´s thesis is design a microphone preamplifier which uses vacuum tube as a main amplifying element. Part of the work is theoretical assumptions for the optimal design and implementation of peripheral involvement, comparing the properties of components used and the resulting parameters of modeled device. The thesis also includes a proposal of the source unit for supplying all parts of the preamplifier. The results are accompanied by circuit simulations and laboratory measurements of the main parameters of the designed device.

Over the last decade, electronics operating at high temperatures have been increasingly demanded to support in situ sensing applications such as automotive, deep-well drilling and aerospace. However, few of these applications have requirements above 460 °C, as the surface temperature of Venus, which is a specific target for the seismic sensing application in this thesis. Due to its wide bandgap, Silicon Carbide (SiC) is a promising candidate to implement integrated circuits (ICs) operating in such extreme environments. In this thesis, various analog and mixed-signal ICs in 4H-SiC bipolar technology for high-temperature sensing applications are explored, in which the device performance variation over temperatures are considered. For this purpose, device modeling, circuit design, layout design, and device/circuit characterization are involved. In this thesis, the circuits are fabricated in two batches using similar technologies. In Batch 1, the first SiC sigma-delta modulator is demonstrated to operate up to 500 °C with a 30 dB peak SNDR. Its building blocks including a fully-differential amplifier, an integrator and a comparator are characterized individually to investigate the modulator performance variation over temperatures. In the succeeding Batch 2, a SiC electromechanical sigma-delta modulator is designed with a chosen Si capacitive sensor for seismic sensing on Venus. Its building blocks including a charge amplifier, a multiplier and an oscillator are designed. Compared to Batch 1, a smaller transistor and two metal-interconnects are used to implement higher integration ICs in Batch 2. Moreover, the first VBIC-based compact model featured with continuous-temperature scalability from 27 to 500 °C is developed based on the SiC transistor in Batch 1, in order to optimize the design of circuits in Batch 2. The demonstrated performance of ICs in Batch 1 show the feasibility to further develop the SiC readout ICs for seismic sensor system operating on Venus. / <p>QC 20170911</p>

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.

The main topic of the thesis is to suggest and realize the measuring card with analog inputs and outputs. In the first part of this thesis we are concerned with key-elements of measuring cards, respectively ADC and DAC, and here are explained all their activities. Then we attend of choosing parts for suggested measuring card as is voltage reference, power supply and operational amplifier. Among others we are concerned with a question of protecting inputs against overvoltage and reversing of polarity and beside against disturbance. Then follows analysis of used microcontroller ADUC831 with description of its used outskirts. Here is described the stored for measured samples of MMC memory, how to work with it and the programme service. The last chapter describes suggested firmware and servicing programme for PC. In fine we value the quality of measuring card and its mistakes.

The present thesis is focused on all pass filters. The principle of all pass filters, their properties, the design of nth degree of these circuits will be analysed in succession and then some of functional blocks, by which these structures can be made, will be described. After that, the allpass filters will be designed and simulated in program OrCAD PSpice. First of all, the analysis will be performed with ideal components, then with real components. After that, the sensitivity and tolerance analysis will be made and the influence of parasite effects on circuit parameters will be examined. Once the experiments are finished, the design of Printed Circuit Board's (PCB) will be realized. Circuit showing the best parameters will be chosen for the design.

This works focusesof the propose and realization device for drive four quadrant bridge convertor with transistors IGBT. Final propose include drive unipolar and bipolar, choice between direct or alternative modulation.

This work deals with the design of a 10-zones equalizer with optimized frequency characteristics with a spectrum audio analyzer. In this work the problem of processing audio signals using equalization for filtering the interference frequencies, correction of frequency cover signal boost or suppression of the required zones of the audible spectrum are also analyzed. The influence of subjective perception of sound intensity of the audio signals reproduction and its use in working with equalizer is discussed too. The work describes the principles and usage of the audio-analyzer as a tool for the optimization of the audio equalization setting when ensuring the appropriate listening conditions of music reproduction, spoken word, sounds, etc. It also focuses on the signal source for testing audio-chains, their generation and measurement using the audio analyzer. The equalizer equipment, audio-analyzer generator of reference signals equipment and power supply are designed as a single unit.

This dissertation thesis deals with design of new functional blocks usable in area of analogue signal processing, focusing on sensor signal processing. Versatility of these circuits will find applications in programmable analogue array structures that will be possible to control and configure via a digital signal. Hereby build-up array would be fully a reconfigurable digital control system for sensor signal processing and usable for a wide range of different sensors. It offers possibility to build-up a control code for each specific sensor system, with which it would be possible to achieve optimal results of the entire system and consequently place the system on a chip. The presented programmable array is designed from configurable analogue blocks. The current feedback circuits, which in a suitable configuration can operate in voltage or current mode, are used here. This allows to achieve very good results in the systems with very low power supply, which is closely associated with mobility and autonomous behavioral (that are very important and observed parameters today) of the entire sensor-based framework. The work deals in detail with particular blocks, which are described theoretically and evaluated for using in the programmable analogue array. Design of the structure of programmable analogue array as well the use of these circuits in the part of whole system (that will be realized on a chip) are presented at the end of this thesis.

The diploma thesis focuses on optical fiber sensors with detailed preview of the turbidity sensor, its design and testing. The introduction deals with the general theory of fiber sensors and measurement methodology of physical variables. This part is followed by a charter focusing on the possible ways of measuring turbidity. Furthermore, the diploma thesis introduces design of the new turbidity sensor which is realized with consideration of the industrial usage and future application to the automated process of beer production. It also includes a detailed description of the hardware and software sensors created within this thesis. The last section is devoted to a calibration and testing functionality of turbidity sensor.