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C — Setup and Hold Time (Internal data sampling window) defined by Rspos (receiver input strobe position) min and max

Tppos — Transmitter output pulse position (min and max)

RSKM = Cable Skew (type, length) + Source Clock Jitter (cycle to cycle) (Note 12) + ISI (Inter-symbol interference) (Note 13)

Cable Skew — typically 10 ps–40 ps per foot, media dependent

Note 12: Cycle-to-cycle jitter is less than 150 ps at 85 MHz

Note 13: ISI is dependent on interconnect length; may be zero

FIGURE 11. Receiver Skew Margin

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FIGURE 12. TJCC Test Setup - DS90C387R

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FIGURE 13. Timing Diagram of the Input Cycle-to-Cycle Clock Jitter

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