How Do You Identify The Perfect Quartz Crystal?
Both developers and buyers face problems in choosing the right quartz crystal. They aren't aware of the exact specifications for each quartz group and there are numerous subcategories in each quartz group. It is simple to identify the best quartz crystal by focusing on six important aspects.
It's a good idea to research the characteristics of frequency control components prior to beginning the process of designing a quartz oscillator. Six aspects must be taken into consideration when looking for a reliable quotation. Once you prefer to find out the latest information about Healing Crystals, you have to click over here at SoulAlign site.
Six criteria for selection:
Packaging form: This package is hermetically sealed and wrapped from metal. It can be used using quartz crystals (THT) with a frequency of 32.768MHz or greater. With this type, the packages are typically over 6mm long, and are therefore not suitable for space-saving applications. Quartz crystals that are used in SMD packages provide significantly smaller structures, measuring as a matter of fact 1.6x1.2x0.3mm.
Note: Quartz oscillators can't be diminished in size indefinitely due to technical reasons. not all quartz crystals are accessible in every form of mounting.
* Frequency: The most common quartz crystals are found between 32.768kHz to around. 200MHz. Higher frequencies quartz crystals are usually available in smaller sizes for mounting. So, for example, an 8MHz quartz crystal measures around 7x5mm while the 20MHz quartz crystal is 2x1.6mm important for circuit design.
* Operating temperature range: Quartzs show some degree of temperature dependency. Limit values in the datasheet may be exceeded. However, problems will not always happen immediately, and operation may continue to run depending on the circumstances. But, this does not prevent the application from remaining within the guaranteed tolerances.
* 25degC frequency tolerance The manufacturer defines the frequency tolerance. It is the maximum expected total deviation from rated frequency at ambient temperatures above 25degC. Operating within the permitted parameters ensures that the quartz's oscillating frequency crystals remains within the acceptable range. The most suitable solution for your specific needs can be determined by choosing the correct frequency tolerance.
* Frequency stability over the temperatures of operation: Manufacturers define both frequency stability across the operating temperature range and frequency deviation in ppm for each temperature variation. So, developers can take temperature effects into consideration ahead of time and adjust the frequency if needed.
Tip: For particularly high demands on frequency stability, it makes sense to look at using temperature-compensated crystal oscillators.
* Load capacitance: The proper load capacitance (CL) of the oscillator circuit (= capacitance C, which the quartz oscillator recognises in its connections) is essential in ensuring that the oscillator maintains the frequency as precisely as it is possible. Quartz crystals are cut by the manufacturers to allow them to work within the limits of the load capacitance. Specific modifications to the capacitance of the load makes it possible to change the frequency of the quartz crystals, allowing them for particularly high frequency-precision demands. This characteristic is known as "pullability" in quartz crystals. However, it is not guaranteed when you exceed the tolerance of sensitivities.