At high data-rates, electrical connections suffer from
from frequency dependent propagation delay, skew, cross-talk and ground-loop
distortion because of the unavoidable physical barriers of the line
impedance and capacitance. The figure of merit for a communication channel,
the bit-rate distance product, is limited in the case of PCB tracks to
around 0.5 GHz.m . The
solutions to overcome this limitation are becoming increasingly heroic.
Gigabit Ethernet, for example, requires multilevel coding on 4 wire pairs,
sophisticated digital adaptive filtering techniques and echoelimination.
Pushing up the bitrate of electrical interconnects by advanced techniques
such as adaptive equalisation and pre-emphasis is a viable route if the
connection density is low as in the case of LANs. However, these techniques
becomes increasingly difficult when real estate is sparse such as for the
traces and connectors on a PCB.
While new techniques, such as the
MicrocoaxTM system by Viasystems, are set to extend electrical bitrate
products, few people see practical electrical systems as being capable of
delivering the soon to be required 10 GHz.m.
If you don't find what you're looking for,
Contact Us.
We may have a suitable product that's not listed, or we may be
able to develop a material to fit your specific needs.
Tel : (02)2217-3442 / Fax : (02)2704-4070
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