Xtal frequency!!!!!!!

[grittinjames]

xtal frequency

Hi,

Is possible to vary Xtal frequency slightly by voltage?
Thanks

 

[unkarc]

xtal change frequency

Yes. Xtal oscillators whose frequency can be controlled by voltage are called VCXOs (voltage controlled Xtal oscillators).
Usually varicap diodes are used for this purpose. See some link on this topic:

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rgds, unkarc

 

[FvM]

xtal frequency table

For small variations, a crystal oscillator with an external "pull" varicap diode is a usual technique. You can expect several 100 ppm maximum, sufficient to adjust an oscillator to it's nominal frequency in a small bandwidth PLL.

 

[grittinjames]

varying a xtal frequency

Hi FVM,Please explain little deep .
\
Thanks

 

[FvM]

xtal varicap

See usual VXCO circuit, e. g. page 5 of the below Linear application note:
https://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1154,C1002,C1223,P1240,D4108