iMX8M-PLUS: Accuracy of 24 Mhz on the module


We want to use CLK_24M_REF_OUT (pin 208) 24 Mhz clock output to feed our FPGA if it is possible.
But we need to know the accuracy of this clock like initial offset error in ppm, temperature coefficient and aging parameter. I couldn’t see them in the module datasheet. Is it possible to share them?

Thank you.

Hello @Fide ,

Could you please tell us from where you have this term CLK_24M_REF_OUT from? We could not locate that in the device tree or the Data sheet.

But pin 208 also has an alternate function CCM_REF_CLK_24M. We will meanwhile check internally, where we could source this info from.

Best Regards,

Dear @saijanani.tx ,

I took the pin name from Toradex Pinout Designer. Basically It refers to CCM_REF_CLK_24M alternate function like you mentioned.

Thank you,

Hello @Fide ,

We only have the specifications of the crystal:
Tolerance @25°C: 30ppm
Frequency Stability: 30ppm
Operating Temperature: -40 to 85°C
Aging per year: 3ppm max
Unfortunately, we do not have the temperature coefficient. Please also keep in mind that the external circuit (e.g. load capacitance) can influence the clock frequency.

I hope this helps!

Best Regards,

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Thank you for all these information.