AnsweredAssumed Answered

8M Mini 24MHz crystal load capacitance

Question asked by adevries on Sep 4, 2019
Latest reply on Sep 11, 2019 by igorpadykov

Hello,

 

I'm trying to choose a 24MHz crystal to use with the 8M Mini, but I am having difficultly determining which crystals would be acceptable to use. While the datasheet recommends a crystal with a typical Cload of 12pF, the eval kit uses a crystal with a Cload of 9pF. If I am interested in using a crystal with a Cload that isn't 12pF, how can I go about determining if it will work with the 8M Mini?

 

Additionally, when adding load capacitance, it's important to match the load capacitance listed on the crystal datasheet, correct?

 

So, if the crystal CL = 9pF, then I would pick C1 and C2 such that this equation:

 is satisfied, right? In this case, Cs is stray capacitance, Ci is the input capacitance, and Co is the output capacitance.

 

If so, does anyone know what the pin capacitance is for pins 24M_XTALI and 24M_XTALO? 

 

Thanks

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