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Crystal choice

Hello,
I ve made a custom nrf52832, but ive face a lot of problemes : when logs is on the BLE is off(its not advertising) , I m not able to see it on my app.
when my module of gps/gsm sening the data via Tcp the BLE stops advertising until it the data is sent.
I think it's because of the crystal choice.
so Ive decide to reDesign my card and to specify more the values of the crystals, not only the 32.768kHz  and 32MHz, I've seen that I should specify the tolerence and ..
so ive see that the recommended one is : 

32 MHz, Cl=8 pF, total tol. ±40 ppm

and

32.768 kHz, CI=9 pF, total tol. ±50 ppm

but in the nrf52 dk ive seen difference things : XTAL SMD 3215, 32.768kHz, 9pF, ±20ppm  and  XTAL SMD 2016, 32MHz, Cl=8pF, Tol: ±10ppm, Stab: ±10ppm
so ive become confused what i should do ?
can some one help me why this values what make difference? , is the crystals are the main puprose of my problemes ?
  • Hi,

    What kind of crystals are you using? Have you check the recommended load capacitance on the crystal datasheet? It could be you are using a crystal load capacitor value that doesn't match the load cap recommeneded by the crystal manufacturer.

    About the crystal recommendation, the maximum recommended tolerance is ±40 ppm for 32MHz and ±50 ppm for 32kHz as you pointed out from the PS, but it's perfectly find to use a crystal with lower tolerance.

    Best regards,

    Marjeris

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