Altera JNEye User Manual
Page 172
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Figure 3-21: CTLE Output Hybrid Eye Diagram and BER Analysis with CDR Recovered Clock
When you enable CDR in a receiver, the reference clock’s phase noise is shaped and filtered with the
CDR’s response. The following figure shows the characteristics of phase noise at the output of the
reference clock (blue), after the transmitter PLL (red), after the transmitter PLL plus the transmitter’s
intrinsic jitter (red), after the RX CDR (cyan), and after the RX CDR with transmitter and receiver’s
intrinsic jitter (black). The associated random jitter from the phase noise power spectrum at each of the
above stages was calculated and displayed in the text below the plot.
UG-1146
2015.05.04
Analysis
3-21
Tutorial: PCI Express 8GT
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