How can I determine the motional C of the crystal model?

[davidwong]

How can I determine the motional C of the crystal model.
From the crystal vendor spec. i can not find any motional C or motional L value.
How do I build the crystal model for my simulation?

Thx

 

[flatulent]

Re: crystal model

You will need a plot of impedance vs frequency. The resistance at zero phase angel is the R in the equivalent circuit. Then the bandwidth at the 45 degree angle points can be used along with the frequency of zero phase to get the LC values in the series circuit.

 

[unkarc]

Re: crystal model

Hi,

Maybe the last page of this paper at the link below helps you to achieve flatulent's advice easily in practice:

**broken link removed**

Another method is shown in page 2 of this paper at this link:

https://www.euroquartz.co.uk/pdf/tech-notes.pdf

unkarc