MHz~MHz. 30Max. Fundamental/AT. MHz~MHz. 60Max. Third. Overtone /AT. Mechanical characteristics. Resistance to shock. that may be provided in Freescale Semiconductor data sheets and/or specifications can and do vary in different applications and actual performance may vary. series and range associated to this part. 49USMX Series. Technical Datasheet: MHZ 49USMX/30/50/40/18PF/ATF Datasheet. See all Technical Docs.
|Published (Last):||8 August 2004|
|PDF File Size:||16.80 Mb|
|ePub File Size:||15.52 Mb|
|Price:||Free* [*Free Regsitration Required]|
For processing involving etching, e. The specific characteristics depend on the mode of vibration and the angle at which the quartz is cut relative to its crystallographic axes.
Very small crystals for high fundamental-mode frequencies can be manufactured by photolithography. The composition dayasheet the crystal can be gradually altered by outgassing, diffusion of atoms of impurities or migrating from the electrodes, or the lattice can be damaged by radiation.
They dztasheet also often incorporated in a single package with the crystal oscillator circuit, shown on the righthand side. Note that these points imply a subtlety concerning crystal oscillators in this frequency range: Mechanical stresses also influence the frequency.
Such swept crystals have a very low response to steady ionizing radiation.
By the s virtually all crystals used in electronics were synthetic. The orientation of the cut influences the crystal’s aging characteristics, frequency stability, thermal characteristics, and other parameters. Techniques minimize the phase noise in crystal oscillator circuits.
Figure 5 illu strate s a block diagram of th e oscillator circuit w ith th e crystal as p a rt of th e PIfeedback netw ork. J cut is made of two quartz plates bonded datasheer, selected to produce out of phase motion for a given electrical field.
The large ones are large enough to allow some mobility of smaller ions and molecules through the crystal.
Without the load capacitance, the resonant frequency is higher. High-purity quartz crystals are grown with especially low content of aluminium, alkali metal and other impurities and minimal defects; the low amount of alkali metals provides increased resistance to ionizing radiation. Quartz crystal oscillators were developed for high-stability kda references during the s and s.
Butler oscillator Pierce oscillator Tri-tet oscillator. Patent 5,Issue date: Retrieved August 24, Swept crystals are crystals that have undergone a solid-state electrodiffusion purification process. It is inversely dependent on the frequency, and on the constant that is dependent on the particular cut.
Views Read Edit View history. A crystal is a solid in which the constituent atomsmoleculesor ions are packed in a regularly ordered, repeating pattern extending in all three spatial dimensions.
A crystal’s frequency characteristic depends on the shape or “cut” of the crystal. Slow chemical reactions may occur on or in the crystal, or on the inner surfaces of the enclosure.
The output frequency of a quartz oscillator can be either that of the fundamental resonance or of a multiple of that resonance, called a harmonic frequency. Presence of etch channels and etch pits degrades the resonator’s Q and introduces nonlinearities. Another method commonly used is electrochemical increase or decrease of silver electrode thickness by submerging a resonator in lapis lazuli dissolved in water, citric acid in water, or water with salt, and using the resonator as one electrode, and a small silver electrode as the other.
KDS+ datasheet & applicatoin notes – Datasheet Archive
Crystal Parameters The operation ofcharacteristics of the piezoelectric crystal and the on-chip crystal oscillator circuitry designed into the RTC, Xe, with respect satasheet frequency for KDS ‘s DT crystal. Crystal is the common term used in electronics for the frequency-determining component, a wafer of quartz crystal or ceramic with electrodes connected to it. Modern Dictionary of Electronics, 7th Ed.
This section is too long. Requires an oven, does not operate well at ambient temperatures as the frequency rapidly falls off at dayasheet temperatures. The oscillator circuits 2 Crystal frequency tolerance Aug. An inappropriate value of the tank capacitor caused the crystal in a control board to be overdriven, jumping to an overtone, and causing the train to speed up instead of slowing down.
Only odd numbered overtones are used. Shinohara; Hideo Iwasaki; Carlos K. Factors outside of the crystal itself are e. Dztasheet factors influencing the frequency are the power supply voltage, load impedance, magnetic fields, electric fields in case of cuts that are sensitive to them, e.
The frequency of the crystal is slightly adjustable “pullable” by modifying the attached capacitances. Patent 3,Issue date: Daasheet growth defects source as supply of hydrogen ions for radiation-induced processes and forming Al-OH defects.
Sodium and iron ions can cause inclusions of acnite and elemeusite crystals.
A major reason for the wide use of crystal oscillators is their high Q factor. Crystals can be grown as Y-bar, with a seed crystal in bar shape and elongated along the Y axis, or as Z-plate, grown from a plate seed with Y-axis direction length and X-axis width. The short-term stability is measured by four main parameters: Has reasonably low temperature coefficient, widely used for low-frequency crystal filters. High-intensity radiation can stop the oscillator by inducing photoconductivity in the crystal and transistors; with a swept crystal and properly designed circuit the oscillations can restart within 15 microseconds after the radiation burst.