what is the importance of crystal frequency stability and tolerance

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The frequency error of crystal oscillator is one of the important parameters of crystal oscillator. We usually use the ppm value to indicate the extent to which the crystal frequency will deviate from the standard frequency. The smaller the ppm value mean precision is high. 

The frequency difference of crystal oscillator generally refers to two aspects: frequency tolerance and frequency stability .

frequency tolerance :

The allowable deviation of crystal oscillator between operating frequency and  standard frequency at 25 ℃.  Usually the frequency tolerance is ± 10ppm, ± 20ppm ,± 30ppmand ± 50ppm

In the crystal oscillator datasheet of XTALONG . we often see that the frequency tolerance is ± 10ppm~± 50ppm, actual the value is more smaller.  Like datasheet is discription standard is ± 30ppm, and the crystal oscillator in IPQC process  can achieve ± 5ppm.

 

frequency stability .

In different temperature ranges (- 20~70 ℃) ordinary/civil crystal oscillator; - 40~85 ℃ industrial temperature; - 55~125 ℃ automotive crystal.

the allowable deviation of frequency stability between operating frequency and standard frequency, unit is the same ppm. When the operating temperature range of the crystal oscillator produced by XTALONG is - -20~70 ℃, the frequency stability of the crystal oscillator can be controlled within ± 10~± 15ppm.

On the whole frequency stability should be to considered important data ,Because of every electronic product has its own heat dissipation and environmental temperature when it is working. According to different product applications, select the suitable frequency tolerance and frequency stability can ensure that the output frequency and various performance. If you don’t have any ideas , you can contact us for help .PCBA matching also can improve your design.


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