Download or read book Temperature Compensated Crystal Oscillator TCXO Design Aids Frequency Temperature Resonator Characteristics as Shifted by Series Capacitors written by Arthur Ballato and published by . This book was released on 1977 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: Resonators for TCXO application are required to have accurately-characterized frequency-temperature (f-T) curves and equivalent network parameters. This report describes how the circuit parameters, critical resonator frequencies, and temperature coefficients depend on material constants of the crystal and geometrical factors. These constants are tabulated for AT- and SC-cut quartz. It further explains the observed f-T curve shift between resonator operation with and without series load capacitors. Simple relations are given for treating this effect, along with charts and other design aids. These are used in a practical example involving an AT-cut resonator for a typical TCXO application. (Author).
Download or read book Crystal Oscillator Design and Temperature Compensation written by Marvin Frerking and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: Crystal oscillators have been in use now for well over SO years-one of the first was built by W. G. Cady in 1921. Today, millions of them are made every year, covering a range of frequencies from a few Kilohertz to several hundred Mega hertz and a range of stabilities from a fraction of one percent to a few parts in ten to the thirteenth, with most of them, by far, still in the range of several tens of parts per million.Their major application has long been the stabilization of fre quencies in transmitters and receivers, and indeed, the utilization of the frequency spectrum would be in utter chaos, and the communication systems as we know them today unthinkable,'without crystal oscillators. With the need to accommodate ever increasing numbers of users in a limited spectrum space, this traditional application will continue to grow for the fore seeable future, and ever tighter tolerances will have to be met by an ever larger percentage of these devices.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1977 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A New Frequency Temperature Compensation Method for Oscillators written by T. Kudo and published by . This book was released on 1983 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper describes a new frequency temperature compensation method for crystal oscillators. The method is applicable to resonators with second order or third order frequency temperature characteristics. Hence, an oscillator with an AT cut, a BT cut crystal unit or a surface acoustic wave resonator (SAWR) can be efficiently compensated. A conventional temperature compensated crystal oscillator (TCXO) uses an expensive variable capacitance diode (varactor) with good linearity as well as many thermistors. Considerable efforts have been devoted to developing a new reactance circuit to replace the varactor. It was found that a series circuit, involving a capacitor and a silicon diode, has the same characteristics as a varactor, and its linearity could be easily adjusted. In the case of an AT cut crystal unit with third order frequency temperature characteristics, compensation over a wide temperature range can be achieved by using two series circuits.
Download or read book A New Digital TCXO Temperature Compensated Crystal Oscillators Circuit Using a Capacitor Switch Array written by T. Uno and published by . This book was released on 1983 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recently, Digital TCXOs have been studied extensively, because of their high stability and rapid start-up time. However, they have the disadvantages of large circuit scale and high power dissipation. To solve these problems, it is necessary to develop an LSI circuit for TCXOs. This paper describes a new digital TCXO structure suitable for a C-MOS integrated circuit. A new and simple temperature compensation algorithm is also proposed. The TCXO circuit proposed here has a new crystal oscillation circuit directly controlled by a digital signal. This makes it possible to eliminate D/A converter and varactor diode used in conventional digital TCXOs. The new oscillation circuit is composed of an amplifer, a quartz resonator and a capacitor-switch array.
Download or read book The Journal of the Acoustical Society of America written by and published by . This book was released on 1977 with total page 1334 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1977 with total page 784 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government reports annual index written by and published by . This book was released on 199? with total page 908 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Understanding Quartz Crystals and Oscillators written by Ramon M. Cerda and published by Artech House. This book was released on 2014-05-01 with total page 325 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quartz, unique in its chemical, electrical, mechanical, and thermal properties, is used as a frequency control element in applications where stability of frequency is an absolute necessity. Without crystal controlled transmission, radio and television would not be possible in their present form. The quartz crystals allow the individual channels in communication systems to be spaced closer together to make better use of one of most precious resources -- wireless bandwidth. This book describes the characteristics of the art of crystal oscillator design, including how to specify and select crystal oscillators. While presenting various varieties of crystal oscillators, this resource also provides you with useful MathCad and Genesys simulations.
Download or read book A New Approach to a High Stability Temperature Compensated Crystal Oscillator written by S. Schodowski and published by . This book was released on 1970 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report describes a compensation approach based on the introduction of controlled nonlinearity into the TCXO's frequency-voltage tuning characteristic by using a pair of varactor diodes and a fixed bias source. The result is considerable simplification of the temperature-compensation process for a TCXO using a fundamental AT-cut crystal unit. The simplification comes about by transformation of portion of the classic cubic voltage correction function to a monotonic function which then can be approximated to a high degree of accuracy with one or two '3-point' network segments, using a given thermistor in each. A stability of plus or minus 5 x 10 to the minus 8th power (5 to 80C) was obtained in one case where the required monotonic compensation function was generated in two segments. In another example, a stability of plus or minus 1 x 10 to the minus 8th power was easily obtained by compensating over a plus or minus 10C range about the upper turnover temperature. (Author).
Download or read book Quartz Crystal Oscillator Circuits Design Handbook written by D. Firth and published by . This book was released on 1965 with total page 552 pages. Available in PDF, EPUB and Kindle. Book excerpt: The object of this handbook is to assemble a set of design methods for crystal oscillators in the frequency range of 1 KC to 200 MC with the aim of facilitating design, eliminating crystal unit misapplications, and reducing design costs. The handbook is not directed at the design of ultra-stable crystal oscillators, but rather at the non-temperature controlled, medium frequency stability oscillator commonly in use in many types of communications equipment. The handbook contains discussions of: (1) The electrical characteristics of crystal units, condition of usage, and methods of measurement. (2) Characteristics of tube and transistor amplifiers. (3) Characteristics of impedance transforming networks. (4) Detailed design information on series resonance and anti-resonance oscillators. (5) Design examples together with experimental evaluation data covering most of the 1 KC to 200 MC range. (Author).
Download or read book Temperature Compensated Crystal Oscillator Survey and Test Results written by V. Rosati and published by . This book was released on 1983 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: To assess the availability and quality of moderate and high precision TCXO, a variety of oscillators was purchased and tested. Tests included frequency-temperature stability and aging. Oscillators in the 1 to 5 ppm stability range were found to conform to specifications, except that aging characteristics were widely variable. Oscillators between 0.5 ppm and 1 ppm did not fare as well. Significant percentages were out of specification. Aging for these oscillators was better, but still disappointing in many cases. No correlation between price and performance was found. Users are cautioned to carefully specify and test candidate oscillators before designing them into systems. (Author).
Download or read book Comparison Among Precision Temperature Compensated Crystal Oscillators written by and published by . This book was released on 2005 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: There are different precision temperature compensated crystal oscillators showing the frequency-temperature stability better than 1x10( -6) in a very wide temperature range. To choose the suitable oscillator one should consider its frequency-temperature stability, power consumption, size, cost, phase noise and other specifications. According to a lot of experiments and comparisons, as the precision TCXO, double compensated TCXO which combines analog and digital compensation approaches together is more competitive in cost, size, stability and mass production compared with ordinary precision TCXO, DTCXO and MCXO based on AT cut crystals. It is difficult to use ordinary TCXO to get a very good frequency-temperature stability, but its repeatability can be good with suitable components and circuits, and quantization error does not exist in it. Therefore it is possible to be compensated further.
Download or read book Externally Compensated Crystal Oscillator ECXO Study written by O. J. Baltzer and published by . This book was released on 1984 with total page 69 pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary objective of this contract was an investigation and exploratory development of an externally compensated crystal oscillator (EXCO) in which frequency-temperature compensation of the C-mode frequency of an SC-cut quartz crystal is achieved by utilizing the concurrent B-mode frequency as a highly sensitive digital temperature sensor. The digitized B-mode output, used in conjunction with a microcomputer and a stored frequency/temperature look-up table or a suitable compensation algorithm, is able to provide precise and accurate clock corrections over a much wider range than that possible with a conventional TCXO oscillator (a temperature compensated oscillator which employs a voltage-variable capacitor for direct oscillator frequency control).
Download or read book Introduction to Quartz Frequency Standards Revision written by John R. Vig and published by . This book was released on 1992 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: The fundamentals of quartz frequency standards are reviewed. The subjects discussed include: crystal resonators and oscillators, oscillator types, and the characteristics and limitations of temperature-compensated crystal oscillators (TCXO) and oven-controlled crystal oscillators (OCXO). The oscillator instabilities discussed include: aging, noise, frequency vs. temperature, warmup, acceleration effects, magnetic field effects, atmospheric pressure effects, radiation effects, and interactions among the various effects. Guidelines are provided for oscillator comparison and selection. Discussions of specifications are also included, as are references and suggestions for further reading.
Download or read book Frequency Temperature Compensation Techniques for Quartz Crystal Oscillators written by C. D. Dominguez and published by . This book was released on 1966 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this program was to advance circuit techniques for a new class of ovenless crystal oscillators having frequency temperature stabilities previously achieved in temperature stabilized oscillators consuming several watts of power. Two basic approaches to obtain computer optimized component values for a compensation network required to generate a desired non-linear voltage function, and hence achieve the desired degree of stability, are presented. Two groups of oscillator units, one group built to achieve a design goal frequency stability of + or -1 x 10 to the minus 7th power over the ambient temperature range of -40 C to +75 C and the other group built to achieve a design goal frequency stability of + or -5 x 10 to the minus 8th power over the ambient temperature range of -5 C to approximately +85 C, are discussed. (Author).
Download or read book Design and Development of Frequency Temperature Compensated Quartz Crystal Oscillator 0 1227 u written by C. D. DOMINQUEZ and published by . This book was released on 1965 with total page 87 pages. Available in PDF, EPUB and Kindle. Book excerpt: The need for ovenless quartz crystal oscillators having a deviation less than plus or minus 0.75 parts per million from an absolute frequency over all service conditions, including crystal aging, has been evident for modern communications systems. Knowledge derived from studies on frequecy temperature compensation techniques indicated the feasibility of developing compensated oscillators providing a reduction in both required input power and size over conventional oscillator-oven assemblies. The object of Phase I of this program was to design and fabricate seven exploratory development oscillator models employing such compensation techniques to achieve a frequency stability of less than plus or minus 0.5 ppm over the temperature range of -40C to +65C. This effort was reported in the Phase I Interim Report under this contract. After evaluation of these exploratory models, 18 advanced models were designed and fabricated under Phase II of this program with the same stability over 140C to +75C. This report covers the effort expended and the results obtained during Phase II of this program. The discussion in this report is related to (1) description and test of the Phase II oscillators, (2) design considerations in formulation of Phase II design, (3) component standardization, and (4) overall conclusions and recommendations for this program. (Author).
