For EMI, does unused clock output require termination?/Oscillator question

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jelydonut

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I am trying to get Class B and am just failing by 1-2dB (2nd and 3rd clock harmonic). My oscillator circuit currently does not have any ground fill surrounding it (ground plane below, but no fill on top), so I am assuming that I need to add that with vias around it (picket fence). Also, I have a clock output on the IC I am using, which is currently just a unconnected pad. Should there be termination on that clock line to ground to help with EMI?

Thanks!

jelydonut
 

In case of doubt, the termination of unconnected clock pins will increase ground bounce, power supply ripple and cause an extra current through the terminating resistor, each creating more EMI. Disabling the unused oscillator output would be really helpful.
 

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