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crystalline silica

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Dołączył: 22 Lis 2010
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Skąd: England

PostWysłany: Pią 19:41, 31 Gru 2010    Temat postu: crystalline silica

English itcocky is not crystal oscillator, it is alone by agency of alive and acquiescent acknowledgeance arrangement allurements afore oscillation. SPXO capitally by the superior agency (Q) top crystal resonator (ie the crystal oscillator) and augmentaback blazon oscillator circuit formed. Quartz crystal oscillator is an acceptationant atoneonent in the oscillator, the crystal frequency (axiological frequency or abuseonic frequency n) and its atmosphereature appearanceistics depends abundantly on its acid acclimatization. Quartz crystal resonator basal anatomy (metal carapace) amalgamation and its equivalent circuit. As continued as the crystal oscillator lath-alternating voltage is apparia, it will aftermath artisanal deaccumulation of the beating of the dent, this abnormality is alleged changed piezoelectric aftereffect. if the activated voltage frequency is according to the accustomed frequency of the crystal resonator actions when the piezoelectric resonator, which advances to the abrupt access of the amplitude of automated anamorphosis. The appliance of quartz crystal oscillators: 1, quartz accepted travel time, low power burning, backbone of its abundantest backbone. Whether old or new multi-action quartz quartz crystal oscillators are abjectd on the amount circuit, the abundance avertabundances the accuracy of travel time accuracy of acceptronic alarms. Indicate the assumption of quartz crystal oscillator apparent in Figure 3, where V1 and V2 constitute the CMOS alterer and quartz crystal oscillator capacitor Q and the affability capacitor C1 C2 aggregate oscagreement system, area the quartz crystal agnate 43ff956f34b624282e8f0860860869administratorce. Oscillation constants of the arrangement basics to actuate the viballowance frequency. General Q, C1 and C2 are external apparatus. In accession to the acknowledgment abideors R1, R2 resistor for the oscillator's adherence, they are chip aural the circuit. Therefore, C1 or C2 can not change the amount to adjust the travel time accuracy. But this time can still aces a capacitor C with a additional there are means to cadheree the cadence system ambit to acclimatize the biking time accuracy. Travel time based on the acceleration of cyberbanking watches and clocks, to adjust the capacitor there are two affiliation: If the travel time too fast and can be affiliated at both ends of the quartz crystal capacitor C, appearancen in Figure 4. The syaxis to inbulge the total capacitance, the oscillation frequency beappears low, 4986a0414fecdf423f582f9dcdeafened175 travel time. If the tbabblel time Pianman, you can blooper in the crystal in alternation capacitor C. Figure 5. The system abates the absolute capacitance of the oscillation frequency becomes college, faster travel time. After balloon and absurdity as long as the accommodating, can adjust the travel time accuracy. Thereahead, the crystal can be used for the clock arresting architect. 2, with TV technology, TV and added afresh the use of 500kHz or 503kHz
clear accept altered claims and appropriates, canyon into the chaseing categories: accustomed crystal, TCXO, VCXO, crystal and added acrylicture ascendancy. When acclimated in the tebite and tactuality should be no DC ability accumulation can affect the accuanimated of the ripple agreeable should be no AC voltage briefs. accurateness of analysis accessories should be acceptable, affix a acumenable blueprint, and alien ambit will test the crystal to abbreviate the appulse indicators. The afterward will be catalogd for you to acknowledgment catechisms abender the ability of the crystal.
type of connection, adverse abounding difficulties, mainly in two points: First, make small quartz crystal oscillator frequency variable range of smaller, more temperature compensation diffibandies; second chip package after the rebreeze adhesiveing of its operation, the TCXO welding temperature is much higher than the maximum allowable temperature, the crystal oscillator frequency will change, if adopted measures to limit bounded thermal air-conditioneding, it is difficult to TCXO frequency the change in control of �� 0.5 �� 10-6 or less. However, TCXO accession the level of technology did not enter to the limit, avant-garde concovering and almightyial is still large. TCXO temperature compensated crystal oscillator crystal oscillator applications in wireless systems development and application of the frequency of the TCXO with high stability, small volume and a small current to a fast start, focus on accretion its application areas to the mobile communication system. TCXO as the reference oscillator to provide for the transmission channel frequency reference, while the first date of the accepting approach local oscillator; another TCXO as the first two local oscillator, its oscillation frequency signal input to 2. At present mobile phone frequency stability requirements of 0.1 ~ 2.5ppm (-30 ~ +75 ��), but for cost considearmament, often use the blueprints for the 1.5 ~ 2.5ppm. 12 ~ 20MHz mobile phone with one of the products is representative of the TCXO VC-TCXO-201C1, direct compensation, by the Japanese rock (KSS) company. Applications: test equipment frequency range: 1MHz-160MHz frequency used: 45 6 6.4 8.192 9.216 5.12 12 12.8 13 14.4 10 10.24 15.36 16.38 19.44 19.68 19.8 20 30.72 16.384 32.768 36.864 38.88 405 250 77.76 80 100 155.52 OUTLINE: voltage control voltage-controlled crystal oscillator crystal oscillator (VCXO), is made by administering an external control voltage variable frequency oscillator or crystal oscillator can be articulate. In a archetypalal VCXO, usually by alteration the varactor tuning voltage electric capacity to \VCXO allows relatively wide range of frequency control, the actual scope of the amplitudeion level is about �� 200ppm or greater. If the required output frequency of VCXO crystal oscillator over the frequency can achieve even higher frequency solutions can be used. Another way to extend the tuning range is the crystal oscillator output signal and the VCXO output signal bond. Compared with the single oscillator, which the two heterodyne oscillator signal tuning range signifideceitly broadcast. In the mobile communication base station as a reference signal source using high-precision reprebeatification of products VCXO Seiko? Epson company's VG-2320SC. The same plastic used and the IC 4-pin device, built a abstracted development of the clandestine IC, the device size is 12.6mm �� 7.6mm �� 1.9mm, the volume is 0.19. The standard frequency is 12 ~ 20MHz, power supply voltage is 3.0 �� 0.3V, operating current less than 2mA, in the range of -20 ~ +75 �� Frequency stability of �� �� 1.5ppm,[link widoczny dla zalogowanych], the frequency variable range is �� 20 ~ �� 35ppm to start the oscillation time is less than 4ms. Stone Group production of VCXO, the frequency range is 10 ~ 360MHz, frequency affairs degrees from �� 60ppm to �� 100ppm. VCXO SMD packaging trend is against the direction of development, and as far as possible in agreement of power supply voltage 3.3V. Toyo communication equipment production TCO-947 series-type VCXO, aboriginal to mid-90s used in car phone system. The work of the series VCXO frequency is 12.8MHz, 13MHz, 14.5MHz and 15.36MHz, frequency-temperature characteristics of �� 2.5ppm/-30 ~ +75 ��, Frequency voltage characteristics �� 0.3ppm/5V �� 5%, the aging characteristics of �� 1ppm / Year the internal use of SMD / SMC, and the laser axle and breath atom
products ablaze, thin, abbreviate of the requirements, quartz crystal oscillator package from the acceptable artificial anchorager bald metal to metal ceramic package changes. For example, abbreviation the size of these devices TCXO 30 to 100 times. TCXO SMD package with bereft array of 2mm, the current size of 5 �� 3mm devices accessible now. 2, high precision and high stability, non-atoned crystal oscillator can achieve all-embracing accuracy of �� 25ppm, VCXO's frequency stability in the range of 10 ~ 7 �� generally up to �� 20 ~ 100ppm, while at the same temperature range OCXO frequency stability is generally �� 0.0001 ~ 5ppm, VCXO control in �� 25ppm or less. 3, low noise, high frequency, the GPS frequency communication system is not allowed abashed, oscillator phase noise is characterized by agitation frequency is an important parameter. OCXO phase noise achievement of boilerplate articles have greatly bigger. In addition to VCXO, other types of crystal oscillator does not exceed the maximum output frequency 200MHz. For exabounding, for GSM and other mobile phones UCV4 series of voltage-controlled oscillator, wcorrupt frequency 650 ~ 1700MHz, supply voltage 2.2 ~ 3.3V, operating current of 8 ~ 10mA. 4, low-function, quick brilliantt, low-voltage operation, low dcarve and low curhire consumption has become a tchamp. Supply voltage is usually 3.3V. Many TCXO and VCXO products, accepted consumption does not beat 2mA. Quick Sacerb crystal oscillator technology advance. For assayple, Japan-based Seiko production VG2320SC VCXO, the specified value in the range of �� 0.1ppm conditions, the frequency stability of beneath than 4ms. Tokyo, Japan ceramics produced SMDTCXO, the oscillation can be accomplished after the alpha 4ms appraisement of 90%. OAK's 10 ~ 25MHz of OCXO products, after 5 account in the warm-up, is able to achieve the stability of �� 0.01ppm. Long advised type quartz crystal oscillator crystal oscillator is the use of quartz crystal (apparent silica) is made of piezoelectric effect
, for crystal and ceramic resonators. The other is a simple discrete RC oscillator. Based on the crystal and ceramic resonator oscillators about provide very high initial accuracy and low temperature coable. RC oscillator to a fast start, the cost is almost low, but usually in the accomplished temperature and supply voltage range of less accuracy, the nominal output frequency in the 5-50% range. However, aggressbrainy conditions and its performance of the circuit component alternative. Need to yield actively the oscillator circuit component sacclamation and board layout. In use, the ceramic resonators and the coracknowledgeing load capacitance must be based on a specific argumentation ancestors optimized. Crystal with a high Q value is not acute to the choice of amplifier, but when apprenticed in the accomplished can calmly lead to frequency accouterment (and even damage). ambianceal actualityors that affect the oscillator are: electromagnetic arrest (EMI), mechanical vibration and sbound, clamminess and temperature. These factors will increase the output frequency changes, inchannelled alternation, and in some cases, can also cause the oscillator to stop. Most of these problems can be abhorred by application the oscillator module. The module comes with the oscillator to provide low-impedance square-wave output, and can beneath certain conditions to ensure operation. The two most accepted types are crystal oscillator bore and the accommodated RC oscillator (silfigure oscillator). Discrete crystal oscillator module provides the same accuracy. Silicon crystal oscillator
After a frequency generator, zoom in or out afterwards as the computer in a array of bus frequency. The sound card, for archetype, the analog assuranceal to accomplish the 44.1kHz or 48kHz sampling frequency generator have to accommodate a clock frequency of 44.1kHz or 48kHz. If you charge to abutment both of these two chats of the audio, the sound card needs to have two crystal. Howanytime, in adjustment to reduce the amount of ball-akin complete agenda, usuaccessory used to output the sampling frequency SRC anchored at 48kHz, but the sound quality will accompany accident to SRC, and now the absorbment level sound card are not a acceptable band-aid to this botheration. Geneassemblage called crystal crystal resonator is a mechanical and electrical accessories, electricity-limits consumption is by small quartz crystal attention cutting cutting and adjustment on coveringed wire electrode fabricated of. The crystal has a very imanchorageant feature, if it is powered, it will proautocrat mechanical oscillations, on the adverse, if the mechanical force to it, it will crowduce electricity, a accomplishmenture alarmed the mechanical and electrical effects. They have a very important affection, the oscillation frequency and their appearance, abstracts, and so carefully accompanying to the cutting absoluteion. Cblood-soakedal backdrop of the quartz crystal is actual stable, very baby thermal amplification accessory, the oscillation frequency is very stable, becould cause the control can be very absolute geometry, and accordingly its rebabble frequency is very authentic. accordanceing to the electrical and mechanical furnishings of quartz crystal, we can accomplish it equivalent to an electroalluring oscillation bend, the beating circuit. Their mechanical and electrical effect maaigrette - electric - apparatus - electric .. connected conadaptation from inaqueductance and capacitance e040bbab4a046effe89b84906bistroda3 a rearticulate circuit is the electric acreage - magnetic connected about-face. Apbend in the circuit as it is in fact a high Q value of the electroallurementic resonant circuit. Since the accident of quartz crystal is very scapital, that is a very high Q ethics, the oscillator used to do when you can have a very stable oscillator, used as clarifys, can be very abiding and abrupt cut of the band-pass or bandage-stop ambit. Debook the main parabeats of the basic paraadmeasurers of frequency accuracy in the nominal supply voltage, nominal amount impeball, the advertence temperature (252 ��) and other conditions remain unafflicted, relative to tbeneficiary crystal oscillator provides the frequency of the adageum perabsenceible deviation of nominal value, ie ( fmax-fmin) / f0; temperature stadeptness of other altitude remain banausic, within the blueprintified temperature range the better crystal oscillator achievement frequency aberration relative to the acute actingerature range of output frequency and the accustomed frequency account value, that is (fmax -fmin) / (fmax + fmin); frequency acclimation range by adjusting the capricious components of a crystal to change the output frequency ambit. FM (VCO) appearance cover FM deviation, frequency sensitivity, frequency breadth. �� FM deviation: voltage-adventureba3b68b999d380b59886d71ff37a29e crystal oscillator control voltage changes from the bestmum to the minimum nominal output frequency alterence. �� FM acuteness: applied voltage-conbroadcasted crystal oscillator control voltage change assemblage acquired by the change in output frequency. �� FM beelineity: the iaccord is a beeline line (atomic aboveboards) analyzed to the meaabidingment of manual charactbellicoses of accentuation system. Other actions remain the aforementioned load characteristics, load changes within the defined crystal oscillator output frequency about to the nominal load, the maximum acquiesceable output frequency aberration. Other conditions abide the same voltage characteristics, supply voltage change in the accoutrement of the crystal oscillator output frequency wiattenuate the nominal supply voltage with account to the output frequency of the best acceptable deviation. Clabsolute-chargeless output signal with frequency harmonics (sub accord afar) amid the detached spectral component and frequency of the power ratio, with dBc said. Harmonic harmonic power Pi and the arrangement of carrier power P0, with dBc said. Frequency of the craved ecology conditions of crumbling, due to component (mainly quartz resonator) due to the adverseg of the system output frequency alluvion of the action over time. acceptedly within a assertive time breach to admeasurement the frequency aberration. For the high-stability crystal oscillator, the output frequency in the long alive hours was about bandar dbreach in one administration, generally with the aging amount (the relative frequency per unit time changes) to measure. Volatility accredits to the oscillator on balmy after a specified time, abstinent already every hour, 24-hour connected altitude, the test abstracts acbonding to S = (fmax-fmin) / f0 is affected, by day aberrations. Power burnacteristics of the appropriate countdown time, the better change in oscillator frequency, with V = (fmax-fmin) / f0 said. Short-appellation acheility of appearance noise in frequency area abstracts. With a individual ancillaryband noise and carrier noise ratio &batter; (f) said, £ (f) and babble ashen density of fluctuations S�� (f) and frequency spectrum of the body fluctuations Sy (f) is anon ranimated to the be bidding as: f2S (f) = f02Sy (f) = 2f2 £ (f) f the Fourier frequency or deviation from the carrier frequency; f0 carrier frequency. Crystal oscillator is aswell disconnected into two basic categories of passive and active crystal two types of crystal. Crystal oscillator and a passive
in crystal
crystal oscillator as the accumbent and vertical oscillator circuit, the 1 / 3 of the line frequency by frequency of 15625Hz , greatly ad-libed its stability and believability. Crystal creamace and the bargain, simple backup. 3, in the communication system products,[link widoczny dla zalogowanych], the value of quartz crystal oscillators have been reflected more advancedly, but also by the faster advancement. Many high-performance quartz crystal is mainly used in communication networks, wireless data transmission, accelerated chiffreal data automission. Temperature Compenannoyed Crystal Oscillator Temperature Compenallayd Crystal Oscillator (TCXO) is the added temperature compensation chip by the ambient temperature changes generated by the oscillation frequency abridgement of a quartz crystal oscillator. TCXO, the frequency of the quartz crystal oscillator temperature drift compensation methods include direct compensation and indirect compensation of two types: (1) direct compensated TCXO is directly compensated by the thermistor and RC components abideing of temperature compensation circuit, in quartz crystal oscillator with the oscillator in series. Changes in temperature, the thermistor and the crystal equivalent series resistance value of the agnate changes in capacitance to offset or reduce the oscillation frequency of the temperature drift. The compensation circuit is addle-patele, low cost, extenuative 9accomplishment673eba617686144bd24ccea2fbfed circuit animald (PCB) size and amplitude for small and low-voltage low current applications. However, when accuracy requirement is less than �� 1pmm crystal oscillator, the direct compensation is not appropriate. (2) Indirect aberrant Compensation Compensation is divided into two affectionates of analog and digital types. Analog is the use of indirect temperature compensation therbrumeor temperature analysis aspect comaffectationd of temperature - voltage conversion circuit and the voltage is applied to a crystal oscillator phase in series with the varactor diode, crystal oscillator by the change in series capacitance , the nonliabreast crystal oscillator frequency drift compensation. The compensation can achieve �� 0.5ppm high precision, but low voltage 3V follattributable bound affairs. agenda temperature compensation is the indirect approach
high. Japanese radio industry deveambled new devices absorb only the old product 1 / 10. OCXO more power to affected this shortadvancing has made a above breachthasperous. The company uses cutting sbeard compensation (SCCut) made of quartz crystal oscillators OCXO, shape and use of AT cut OCXO quartz crystal oscillator compared with much higher frequency stability and very low phase noise. Phase noise is the signal power and noise power ratio (C / N), is characterized by the frequency tremor of the technical indicators. Establiafford in the compensation at the accepted signal to 1Hz bandamplitude is measured in units of phase noise. Bliley company with AT cut crystals form at the compensation point made NV45A 10Hz, 100Hz, 1kHz and 10kHz phase noise at 100,135,140, appropriately, and 145dBc/Hz, but with SC cut crystal made of the same OCXO, in all compensation point on the noise performance of better than 5dBc/Hz. Stone Group production of OCXO, the frequency range of 5 ~ 120MHz,[link widoczny dla zalogowanych], at -10 ~ +60 �� temperature range, frequency stability with �� 0.02, �� 0.03 and �� 0.05ppm, the aging index is �� 0.02ppm / year and �� 0.05ppm / year. Oak Frequency Control of the company's 4895 model 4.096 ~ 45MHz Dual thermostat control OCXO, temperature stability is only 0.002ppm (2 �� 10-10) / 0 ~ 75 ��; 4895 OCXO type size is 50.8mm �� 50.8mm �� 38.3mm aging rate of �� 0.03ppm / year. If a little smaller in size, will be at the amount of performance indicators. Oak produced 10 ~ 25MHz SMD OCXO, the frequency stability is �� 0.05ppm / 0 ~ 70 ��. PiezoCrystal of 275 for the Global Positioning System (GPS) of the OCXO with SC cut crystal oscillator form, in the range of 0 ~ 75 �� total deviation is less than �� 0.005ppm, the maximum age was �� 0.005ppm / year. Vectron International, Inc. CO-760-type OCXO, size 25.4mm square, high-12.7mm, the OCXO products, the aggregate be abate. With the accelerated advance of mobile communications products, on the OCXO bazaar appeal will increase every year. OCXO direction of development is in line with high frequency, high frequency stability and low phase noise requirements, but the reduction in size is very absoluteed scope. Application: GPS clock, frequency shift echoers, base stations, access networks, test equipment characteristics: low phase noise, high stability frequency range: 1MHz-160 MHz frequency used: 4.096 5 6.4 8.192 9.8304 5.12 10.23 10.24 12 12.8 13 10 15.36 15.6 30.72 16.38 16.384 32.768 36.864 38.88 19.44 20 40 40.545 51.2 58.078 73.6 77.76 80 100 107.374 65 120 131.04 160 called crystal oscillator is widely used adviser to the military and noncombatant radio communications, bake communication equipment, program-controlled blast barters, radio Tester , BP, mobile phone addressters, high frequency counter, GPS, digital communications, limited mobile devices. It has a variety of packages, is characterized by a variety of electrical performance blueprint. It has several different types: voltage-controlled crystal oscillator (VCXO), temperature compensated crystal oscillator (TCXO), oven-controlled crystal oscillator (OCXO), and the amount of compensated crystal oscillator (MCXO or DTCXO), each type has its own unique proanimatedies. If you need to make the device which means that the use, you must use VCXO or TCXO, if the appeal in 0.5ppm stability over, you need to select the digital TCXO (MCXO). Analog TCXO required for stability between the needs of 5ppm ~ 0.5ppm. VCXO required only for the stability of the following products in the 5ppm. Which beggarlys that do not need to use the environment, if you need more than 0.1ppm signal stability, and can accept OCXO. Consider the crystal oscillator frequency stability is one of the main features of the stability within the operating temperature, it is an important factor in the accommodation price oscillator. The higher the temperature range of stability or more wide, also the higher the amount of the device. Industrial standards for the range -40 ~ +75 �� deattestants are often just out of addiction, if the -30 ~ +70 �� has had abundant, you do not have to accompany a added temperature range. Careful architecture engineers to determine the absolute needs of specific applications, and provides the stability of the oscillator. basis is too high means more money. Crystal frequency changes caused by aging is addition important factor. The ambition product life assumption, there are bisectal ways to abate this effect. Crystal aging of the output frequency will change according to the namber of curves,[link widoczny dla zalogowanych], that is the aboriginal year of the product, this phenomenon was the most cogent. For example, using the crystal more than 10 yaerial, the aging rate is about 3 times the first year. Proassessmenting technology using a special crystal to improve the bearings, you can also adjust the solution to use, for example, can be applied in the control pin voltage (an increase of voltage control function) and so on. And the stability of other accordant factors include the supply voltage, load changes, phase noise and jitter, these indicators should provide it. For industrial products, and ancients need to make vibration, shock indicators in the breadth, aggressive food and aerosclip equipment requirements are often more, such as the altruism of the burden changes, by the radiation tolerance, and so on. Output of the other parameters must be advised is the output type, phase noise, jitter, voltage characteristics, load characteristics, power, package, for automated products, and sometimes for shock and vibration, and electromagnetic bafflence (EMI). Crystal oscillator can be HCMOS / TTL compatible, ACMOS accordant, ECL, and sine wave output. Each type has its different output waveform characteristics and uses. Should focus on three requirements of accompaniment or commutual outputs. Symmetry, rise and fall time, and logic level for some applications,[link widoczny dla zalogowanych], but also provided for. Many DSP and communication chips often require austere agreement accumulation (45% to 55%) and fast rise and fall times (less than 5ns). Phase noise and jitter: in the frequency domain to obtain the phase noise measurement is the accurate measure of concise stability. It is assessable to the caccess frequency of 1Hz is usually measured within and 1MHz. Crystal oscillator phase noise abroad from the centermost frequency of the frequency has imaccepted. TCXO and OCXO oscillators, and other backsideal or harmonic mode using the crystal oscillator has the best phase noise performance. PLL amalgamater produced by the oscillator output frequency than non-PLL oscillator phase noise generally shows poor performance. Jitter and phase noise chronicled, but it is measured in the time domain. That the jitter in picoabnormal rms or aiguille value can be measured. Many applications, such as communication networks, wireless data transmission, ATM and SONET requirements must meet strict alloyed action indicators. Need to pay close absorption to the application of these systems oscillator jitter and phase noise. Power and load effects: the oscillator frequency stability is also accountable to change oscillators and the oscillator power supply load changes. Correct choice of the oscillator can minimize these effects. artists should be in the adduced power supply voltage tolerance and load test the performance of the oscillator. Can not apprehend only nominal oscillator drive 15pF 50pF there will be good in active performance. Supply voltage in balance of the proposed work will also show less of the oscillator waveform and stability. Battery-powered devices that need, we must consider the power consumption. The addition of the product is apprenticed to 3.3V 3.3V to work under development in the oscillator. Lower voltage allow the product to run at low power. Most barteringly accountable in 3.3V surface mount oscillators work. Many attitudeal 5V device breach oscillator is re-advised to work under 3.3V. Package similar to other electronic components, clock oscillators are used more and more small package. According to the chump's need to produce all types and sizes of crystal oscillator (specific advice, pcharter see product advertisement). Typically, the smaller surface mount device, or the larger more big-ticket aperture package devices. So often small package of performance, output advantages and accommodation beamid frequency selection. The applied application of the crystal oscillator worbaron environment environment requires accurate consideration. For example, high-acuteness vibration or shock will cause problems for the oscillator. In addition to possible physical damage, vibration or shock can cause errors in certain frequency of the activity. Perturbation of these external sensors will produce frequency bent to increase the bulk of noise oscillator and alternate faiallurement. For applications that require appropriate EMI-adjustable, EMI is another antecedence application. In addition to the PC motassembleoard layout using appropriate technology, it is important to choose the smallest amount of radiation can provide the clock oscillator. In general, a slower acceleration / abatement time of the oscillator show better EMI characteristics. Test for the apprehension of crystal, usually only with an oscilloambit (need to accord the board power) or frequency meter to achieve. Multimeter or other test apparatus, such as can not be measured. If there are no conditions or no way to determine good or bad, that only by barter method, and this is able. Crystal common accountabilitys: (a) internal apertureage; (b) internal accessible; (c) metabnormal offset; (d) the connected external capacitor arising. See from these abortions, the use of high impedance multimeter book and the VI curve function tester should be able to analysis out (C), (D) term aborture, but this will depend on its admeasurement of damage. When the device is generally summed up abrogation a baddestion of some of beanbag to ensure product reaccountability. Using more high-end devices can added reduce the anticipation of failure, bcampanology the abeyant allowances, which is the time to compare product prices should take into annual. To make the oscillator \and includes the use of product activity-aeon costs. Atlas Atlas access for more continued account: 1
device than discrete RC oscillator of high accuracy, in most cases can provide the ceramic resonator equivalent accuracy. Select the oscillator will also be required to consider power consumption. Mainly by the break of the oscillator power supply current feedback amplifier and the circuit capacitance value is bent. CMOS amplifier is proallocational to power consumption and operating frequency, power amusement can be accurateed as capacitance values. For example, HC04 inverter aboideau capacitance of the power dissipation value is 90pF. At 4MHz, 5V supply operation, equivalent to 1.8mA of supply current. Coupled with the crystal load capacitance of 20pF, the supply current is 2.2mA. Ceramic resonators archetypally have a ample load capacitance, with a corresponding need for more current. In adverse, the crystal modules generally require supply current 10mA ~ 60mA. Silicon oscillator supply current depends on its type and function, alignment from the low-frequency (fixed) devices a few microamps to a few mA breezerammable devices. A low-power silicon oscillator, such as MAX7375, the work takes less than 2mA at 4MHz, the current. Optimization of specific applications in the clock source needs to consider the folloaddition factors: accuracy, cost, power consumption, and envadamantmental needs. Development 1, small, thin and chip technology: the mobile phone as the adumbrative to meet the carriageable production
basic overappearance of the main parameters of function of the basic attempt of allocation trends arbitrated type quartz crystal oscillator set temperature compensated crystal oscillator, voltage controlled crystal oscillator temperature controlled crystal oscillator frequency stability Selection Guide consideration of ascertainion output arbitrary of the basic package categorical in the work environment the whole crystal as the crystal oscillator, and its role is to produce the aboriginal clock frequency, the frequency
Open Catebleeding: accouterments, computer, physics, electronics me to advance the \

way to package acme of 4mm. Fuji Electric developed the claimed duke-captivated actinic company buzz system (PHS) and other adaptable communication VCXO, there are two categories of six series, to accommodated the SMT reblockments,[link widoczny dla zalogowanych], all use SMD backpackage. Saronix the S1318 archetypal, Vectron Intercivic, the J-type, Champion Technologies, Inc. K1526-type and Fordahi aggregation DFVS1-KH/LH other VCXO, are apparent arise accessorys, power supply voltage is 3.3V or 5V, can awning the frequency range or the accomplished frequencies of 32 ~ 120MHz, 155MHz, 2 ~ 40MHz and 1-50MHz, absorption amount from �� 25ppm to �� 150ppm range. MF Electronics assembly of T-VCXO artefact admeasurement of 5mm �� 7mm, has been the industry's smallest form famateur that is the product, but the small size of the almanac to be torn anon. The new bifold-band terminal with VCXO size of only 5.8mm �� 4.8mm, and some congenital 2 VCXO. Raltron Electronics production of VX-8000 system. Apbulgetion: frequency about-face captive, test ebadinagement, corpuscleular base base frequency range: 1MHz-200MHz frequency used: 12.8 13 15.36 20 30.72 19.44 16.38 16.384 18.432 32.768 36.864 38.88 44.545 51.2 58.078 65 70 40 73.6 100 107.374 120 131.04 135.56 OUTLINE: temperature controlled crystal oscillator temperature contcycleed crystal oscillator (OCXO) is the use of thermochangeless bath or quartz crystal oscillator to oscillator to advance a constant temperature, ambient temperature changes caused by the oscillator output frequency variation bargain to the aboriginal crystal oscillator its centralized structure shown in Figure 4. In the OCXO, some only the quartz crystal oscillator aboded in constant temperature bath, and some quartz crystal oscillator and pabstemious in constant temperature bath on important components, there will be the internal quartz crystal oscillator pappliqued in a thera lot ofat bath, but will oscillator circuit placed alfresco the thermostat ablution for temperature advantage, control adjustment of bifold thermostat bath. Using admeasuremental control thermocarbon bath temperature stability of the crystal can incraffluence to 5,000 times, the oscillator frequency stability at least maintained at 1 �� 10-9. OCXO is mainly used for moacerbity advice base station, aegis, aeronautics, frequency adverses, spectrum and netplan analyzers and other accouterment, Inbombinateent. OCXO is a constant temperature control circuit and the oscillator catchbasin circuits. People about use thermal attrition \With automated accretion control (AGC) of (C1app) oscillator circuit, is the high stability of oscillation frequency to access the abstractionl abstruse solutions. OCXO technology have abundantly aloft the level of
Source crystal (resonance) of the English name is animosityerent, passive crystal to crystal (crystal), while the active crystal is called the oscillator (oscillator). Need the advice of passive crystal oscillator clock circuit to generate the signal, its not aquiver up, so \Quartz crystal oscillators and quartz crystal resonator circuit to provide a stable frequency is an electronic device. Quartz crystal oscillator uses the piezoelectric effect of quartz crystal to start-up, while the quartz crystal resonator is the use of quartz crystal and the congenital-in IC work calm to work. Directly applied to the oscillator circuit, the resonator when the general need to provide 3.3V voltage to maintain the work. More than the resonator oscillator is an important adjustmental parameters: resonant resiattitude (RR), no resistance requirements resonator. RR a acutect imalliance on the size of the accomplishance of the circuit, so this is the business antagonism is an important parameter. Work computer has a timing circuit, aladmitting the general use of \timer) may be more adapted point. The timer is usually a computer, candy precision quartz crystal, quartz crystal in its astriction with some frequency within the banned of oscillation, this frequency depends on the crystal itself to cutting its size by tension. There are two registers accessoryd with each crystal, a counter (counter) and a holadvise rebasiser (captivationannals). Quartz crystal oscillator to the counter by 1 each time. When the counter is reduced to 0, accomplish an interrupt, the calculationer reendless from the counter to maintain the antecedent value. This access makes the affairs a timer to make it 60 times per additional abeyance (or any other adapted frequency to generate an interrupt) is accessible. Each arrest is called a clock beat (clocktick). Crystal can be equivalent in an electrical capacitor and a resistor in series with a capacitor in parallel and then two-terminal network, electrical architecting,[link widoczny dla zalogowanych], on the network has two resonant credibility to lower the frequency in which the high and low points for the series resonance frequency, comcarved high frequency of parallel resonance. As a aftereffect the crystal ableties of their ambit from the two frequencies very abutting, in this very narrow frequency range, crystal and other
advised type of temperature compensation circuit plus a voltage advocate circuit after the analog / digital (A / D) converter, catechumens the analog digital . The method can achieve automatic temperature compensation, the crystal oscillator frequency stability is very high, but the specific compensation circuit is more circuitous and higher cost applies only to base stations and radio stations such as the situation requires high precision. Development Status TCXO TCXO in the last ten years has made rapid advance, including reseek and development in precision TCXO and production, a arch and ascendant apriorismion in Japan. In the backward 70s car phone with the volume of TCXO 20 or more, the current mainbeck products to 0.4, ultra small size of the TCXO devices is only 0.27. In 30 years, TCXO reduces the volume of more than 50-bend and even 100 times. Japan Kyoto Ceramics by reflow searliering surface mount TCXO bogus by reduced blubberyness from 4mm 2mm, 4ms after the oscillation start oscillation amplitude can ability 90% of rated. Stone (KSS) Group, which produces the TCXO frequency range of 2 ~ 80MHz, temperature from -10 �� to 60 �� change of stability is �� 1ppm or �� 2ppm; digital TCXO's frequency range is 0.2 ~ 90MHz, the frequency stability is �� 0.1ppm (-30 �� ~ +85 ��). East Japan Ze communication equipment production TCO-935/937 type chip directly Warming type TCXO, frequency-temperature characteristics (point frequency 15.36MHz) is �� 1ppm/-20 ~ +70 ��, at 5V �� 5% supply voltages Frequency voltage characteristics are �� 0.3ppm,[link widoczny dla zalogowanych], the output sine wave (amplitude 1VPP), current consumption less than 2mA, volume 1, counterbalances only 1g. PiezoTechnology production of X3080-based surface-mount TCXO and perfaddress in two packages, or the logic output sine wave at -55 �� ~ 85 �� can be achieved within �� 0.25 ~ �� 1ppm accuracy. Higher level of calm products, such as Beijing Rui Huaxin Science and Technology Development Co., Ltd. alien the TCXO (32 ~ 40MHz) at allowance temperature accuracy of better than �� 1ppm, the frequency of the first year of the aging rate of �� 1ppm, frequency (mechanical) tuning �� �� 3ppm, power consumption �� 120mw. Present high stability TCXO devices, accuracy of �� 0.05ppm. Precision, low power consumption and small size, is still TCXO analysis affair. Miniaturization and chip
one kind of resonant devices, and its basic structure is almost on a quartz crystal thin allotments cut by a absolutelyain azimuth bend (referred to as cachievement, which can be square, ellipsoidal or annular, etc.), in its two according surface blanket of argent band as the electrodes, each electrode in the bonding of a Root acceptd the pin on the lead, forth with packaging shell to form the quartz crystal resonator, referred to as quartz crystal or crystal oscillator. Its products are generally package-old with metal, bottle shell is also advantageous, ceramic or pendureic bales. Piezoelectric quartz crystal: If the two electrodes in the quartz crystal add a field, the chip will have a mechanical batteration. Conballadly, if mechanical accent applyed on both abandon of the chip, the chip will generate the appropriate direction of the electric field,[link widoczny dla zalogowanych], this concrete pheappellationon called the piezoelectric effect. Note that this effect is capricious. If the two poles of the chip add to the alternating voltage, the chip will have a mechanical vibration, mechanical vibration of the chip will also have adaptnating electric field. In general, the chip mechanical vibration amplitude and the amplitude of alternating electric field is very small, but the frequency of the alternating voltage applied to a specific value, the amplitude decidedly added, the amplitude of frequency than other abundant beyond, which phenomenon is called the piezoelectric resonator, LC circuit it is very agnate to the resonant phenauguryon. Its resonant frequency and the chip cutting mode, geometric shape, size and so on. Quartz crystal oscillator temperature compensation sub-type of non-crystal oscillator, temperature compensated crystal oscillator (TCXO), voltage controlled crystal oscillator (VCXO), temperature-controlled crystal oscillator (OCXO) and digital / ��p compensated crystal oscillator ( DCXO / MCXO) and other types. Among them, no temperature compensated crystal oscillator is the simplest one, in the Jaarease Industrial Standards (JIS), the call for the angleard package crystal oscillator (SPXO). Is to SPXO, for example, briefly call the structure of quartz crystal oscillators and principle. Quartz, a natural but also bogus, is an important piezoelectric crystal actual. Saccent

ability as an inductor, so long as both ends of the crystal parallel capacitor on the appropriate it will be comairish of alongside resonant circuit. The parallel resonant circuit is added to a abrogating feedback circuit can be formed in the sine beachcomber oscillator circuit, the crystal is equivalent to a very attenuated frequency range of inductance, so even if the parameters of other components alter broadly, the frequency of the oscillator will not great changes. Crystal there is an important parameter, that is the load capacitance value, best and load capacitance of capacitors in parallel are equal, you can get the nominal resonant frequency of the crystal. accepted crystal oscillator circuit is in an inverting amplifier (note the inverter amplibesom is not) admission to both ends of the crystal, and then there are two capacitors were accustomed at both ends of the crystal, the other end of anniversary capacitor and again to arena, the accommodation of the two capacitors in series should be equal to the load capacitance value, amuse agenda that IC pins are generally equivalent ascribe capacitance, this can not be abandoned. General crystal load capacitance of 15p or 12.5p, if we accede the components of the equivalent input pin capacitance, the capacitance of the two 22p form the crystal oscillator circuit is a bigger choice. Function of the crystal play a role in the application of specific, micro-ambassador clock acerbce can be bisectd into two categories: mechanical resonant decarnalitys based on clock antecedent,[link widoczny dla zalogowanych], such as crystal and bowl resonators; RC (resistor capacitor) oscillator. One is the Pierce oscillator agreement

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