32MHz Quartz doesn't work

[Yann]

Hello everyone,

After having designed a pcb by taking the scheme proposed by the datasheet, I uploaded by the Black Magic Probe, the example code of the SDK "receiver Radio" (functional on dev kit for the nRF52832). the inputs are working perfectly. However, 32MHz quartz does not oscillate. I unsoldered the quartz and the capacitors and measured the voltage on XC1/GND and XC2/GND.  I get 0.8V on both. Is that normal?

Any ideas?

thank you in advance

[Andreas]

Hi,

 

How did you verify that the crystal does not oscillate? Does it stay in the  

    while (NRF_CLOCK->EVENTS_HFCLKSTARTED == 0)
    {
        // Do nothing.
    }

loop?

 

Have you checked that the crystal is not mounted 90 degrees off?

 

Best regards,

Andreas

[Yann]

I'm using this crystal (10PPM) http://www.farnell.com/datasheets/1995792.pdf?_ga=2.26193790.2786657.1561362723-956280504.1515339557&_gac=1.49499732.1561622100.CjwKCAjw0tHoBRBhEiwAvP1GFeeUdlSzykdODDk8zjli6zitWSTcgadeuC31awTscvqW054aozyBnhoCzB8QAvD_BwE

and this cappacitors http://www.farnell.com/datasheets/2746945.pdf?_ga=2.64782444.2786657.1561362723-956280504.1515339557&_gac=1.26930767.1561622100.CjwKCAjw0tHoBRBhEiwAvP1GFeeUdlSzykdODDk8zjli6zitWSTcgadeuC31awTscvqW054aozyBnhoCzB8QAvD_BwE 

is these references ok?

[Andreas]

Hi,

 

These should be fine. Note though that the capacitors value depend on the CL spec of the crystal, they should be equal to 2*CL - 4 pF. The crystal will run if incorrectly loaded, but will be a little more inaccurate.

 

Best regards,

Andreas