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LMK6C: Crystal replacement, schematic review, valid replacement?

Part Number: LMK6C

Hello,

i consider to swap the crystal from an ksz9031 for the next board revision against an LMK6CE025.000CLDF. i am unsure how the schematic have to be changed.

please check my schematic.

Is the LMK6CE025.000CLDF an valid replacement?

Crystal recommendations from the ksz9031:

From the Datasheet

If the 25 MHz reference clock is provided externally, the XI input pin should have a minimum
clock voltage peak-to-peak (VPP) swing of 2.5V reference to ground. If VPP is less than 2.5V, series capacitive
coupling is recommended. With capacitive coupling, the VPP swing can be down to 1.5V. Maximum VPP swing is 3.3V
+5%.

Characteristics Value
Frequency 25 MHz
Frequency Tolerance (max.) ±50 ppm
Crystal Series Resistance (typ.) 40Ω
Total Period Jitter (peak-to-peak) <100 ps

  • Hello, 

    I believe that LMK6CE02500CDLF would be a suitable replacement here. The frequency is 25 MHz ±25 ppm, and the peak-to-peak period jitter is around 13 ps typical. Assuming the Xi pin of the KSZ9031 is high impedance, the output swing should also be close to 3.3V so it should be fine to DC couple and keep the schematic as is. Let me know if you have any other questions.  

    Regards, 

    Connor