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Curvature correction of the BandGap reference output voltage
Žeravík, František ; Háze, Jiří (referee) ; Prokop, Roman (advisor)
This thesis deals with the design of a Brokaw BandGap reference, a BandGap reference in a simple CMOS process, as well as the respective compensation circuits for correcting the curvature of the output voltage. In the theoretical part, the emphasis is mainly on describing the temperature dependency of the UBE voltage of the bipolar transistor and understanding the principle of the elementary BandGap reference. Based on these findings, the function and design of both BandGap references for an output voltage of 1.5 V are described. In the second part, the thesis focuses on describing various methods for correcting the curvature of the output voltage. Based on these methods, the first-order BandGap references supplemented with compensation circuits are designed. In the conclusion, the resulting parameters of the designed BandGap references without correction and with a compensation circuit are summarized and compared.
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An EMC Robust Precise Voltage Reference for Automotive Applications
Krolák, David ; Husák, Miroslav (referee) ; Psychalinos, Professor Costas (referee) ; Horský, Pavel (advisor)
Klíčovou součástí moderních integrovaných obvodů je napěťová reference, která funguje jako srdce analogových bloků poskytující stabilní napětí. Tato disertační práce zkoumá pokročilé metody pro snížení citlivosti nízko příkonových referencí na elektromagnetické interference (EMI) pro automobilová prostředí s širokým teplotním rozsahem. Citlivost na EMI je nežádoucí jev, který může způsobit poruchy elektronického systému. Elektromagnetické rušení se může snadno vázat do obvodu prostřednictvím kabelového svazku a desky s plošnými spoji. Práce poskytuje přehled literatury, návrhy výzkumu a výsledky, které se zaměřují na skryté efekty v napěťovém referenčním jádru, jako je vliv parazitní kapacity z kolektorů bipolárních tranzistorů do substrátu integrovaného obvodu a efekty použitého operačního zesilovače. Jsou uvedena a implementována doporučení pro zlepšení EMI odolnosti napěťové reference. Aby se prokázala platnost navrhovaných vylepšení, byly vyrobeny a změřeny testovací čipy s navrženými napěťovými referencemi v různých technologiích.
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Design of low-voltage supply and reference block based on the bandgap reference
Mudroch, Michal ; Kledrowetz, Vilém (referee) ; Prokop, Roman (advisor)
In this diploma thesis there is elaborated design of low-voltage power supply block using I3T25 technology. The theoretical part describes the basic structures used in the design, using CMOS and bipolar devices. Furthermore, the properties and the analysis used in the evaluation are described. In the design part there is an elaborated design of individual parts, including voltage references, current references, DAC converter, operational amplifier. In the last part, the power supply block is subjected to simulations for verification of temperature compensated output variables and analyzed circuit functionality.
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Design of precise bandgap reference in ACMOS process
Kacafírek, Jiří ; Prokop, Roman (referee) ; Ing. Petr Kadaňka, ON Semiconductor v Rožnově p. Radhoštěm (advisor)
In this thesis the principle of voltage reference especially bangap reference is described. Below are described two circuits of this type designed in ACMOS process. There is handmade evaluation of error analysis to identify main error contributors and also monte-carlo simulation. Also statistical analysis is made on the circuit. Results of all methods are compared. Error of reference voltage is compared for both circuits. Circuit with bigger error is optimized to achieve a better precision. Obtained results showed a good agreement of all methods, which evidences importance of hand error evaluation.
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Design of DA converter with fully differential output in CMOS technology
Mácha, Petr ; Prokop, Roman (referee) ; Kledrowetz, Vilém (advisor)
This diploma thesis deals with the design of eight-bit digital to analog coverter with fully differential outputs in technology I3T25 of ON Semiconductor company. The work contains the description of basic structures and characteristics of digital to analog converters. The main focus of the work is to design a converter and auxiliary circuits at the transistor level. The functionality of designed circuits is verified by simulation environment Cadence.
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Voltage reference based on LTZ1000 IC
Grohoľ, Stanislav ; Musil, Vladislav (referee) ; Hejátková, Edita (advisor)
The thesis deals with the issue of stability of voltage reference based on LTZ1000(A) integrated circuit. At the beginning are specified main parameters of voltage references in terms of stability. The work presents distribution references by architecture and by method of connection to the circuit. Work compares some references of Analog Devices and Linear Technology companies. In work is described voltage reference LTZ1000(A) and its circuits from datasheet. Listed are the main factor that influence the stability of reference, such as temperature, PCB design, Zener diode bias current, airflow and choice of circuit components. Given the description of a design module with the 7 V, 5 V and 10 V output. Made was three samples of PCB. Listed are results from long-term drift and temperature drift measures.
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Weight Measurement with Bathroom Scale Strain Gauges
Šenfluk, Petr ; Fuchs,, Michal (referee) ; Povalač, Aleš (advisor)
The aim of the thesis is weigh measurement using strain gauges from cheap digital scales. Work describes problems connected with using strain gauges as temperature compensation and requirements for accurate voltage reference and summarize function and wiring of chaep digital scales using four strain gauges. Result of work is design of an electrical circuit for weigh measurement using four strain gauges from analyzed scale.
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Controlled laboratory supply
Štibraný, Miroslav ; Petyovský, Petr (referee) ; Macho, Tomáš (advisor)
Master’s thesis deals with design of laboratory supply with precise voltage and current measuring. At the beginning it presents properties, advantages and disadvantages of linear and switching supplies, based on these facts it chooses a linear type of regulator. The design continues with detailed description of power and control analog and digital circuits. The thesis includes description of taking control over the supply from the front panel or through computer. The last part is devoted to measurement results and to presentation of some static and dynamic parameters of the designed supply.
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Precise voltage references
Budáč, Peter ; Ing. Miroslav Horáček, Ph.D., ÚPT AVČR Brno (referee) ; Zobač,, Martin (advisor)
The aim of this thesis is the realization of the workplace to measure long-term stability and temperature coefficient of precision voltage references. It analyses individual solutions precision voltage references and their important parameters for the stability of the reference voltage. It deals with the influence of thermoelectric voltages and methods how to minizme their effect on measurement error . In conclusion it proposes a solution of this measuring workplace, and evaluate the results measuring of long-term stability and temperature coefficient on selected precision voltage references.
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