AC coupling of the oscillator reference clock output to the PS-GTR transceiver reference clock input serves multiple purposes:
•Blocking a DC current between the oscillator and the PS-GTR transceiver reference clock dedicated reference clock input pins (which also reduces power consumption of both parts)
•Common-mode voltage independence
•The AC coupling capacitor forms a high-pass filter with the on-chip termination that attenuates a wander of the reference clock
To minimize noise and power consumption, external AC coupling capacitors between the sourcing oscillator and the PS-GTR transceiver dedicated reference clock input pins are required.