DS92CK16_06 Datasheet, PDF (11/12 Pages) National Semiconductor (TI) – 3V BLVDS 1 to 6 Clock Buffer/Bus Transceiver

Applications Information (Continued)
Surface mount 1% to 2% resistors are best.
PROBING BLVDS TRANSMISSION LINES
Always use high impedance (> 100kΩ), low capacitance
(< 2pF) scope probes with a wide bandwidth (1GHz) scope.
Improper probing will give deceiving results.
CABLES AND CONNECTORS, GENERAL COMMENTS
Use controlled impedance media. The connectors you use
should have a matched differential impedance of about
Zo Ω. They should not introduce major impedance disconti-
nuities.
Balanced cables (e.g. twisted pair) are usually better than
unbalanced cables (ribbon cable, simple coax.) for noise
reduction and signal quality. Balanced cables tend to gener-
ate less EMI due to field canceling effects and also tend to
pick up electromagnetic radiation a common-mode (not dif-
ferential mode) noise which is rejected by the receiver. For
cable distances < 0.5M, most cables can be made to work
effectively. For distances 0.5M ≤ d ≤ 10M, CAT 3 (category 3)
twisted pair cable works well, is readily available and rela-
tively inexpensive.
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