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Altera_Forum's avatar
Altera_Forum
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16 years ago

seriallie over coaxial cable

Hi all, I wonder the SerialliteII can transmit data by a coaxial cable? how will be the max length? Thanks....
Altera_Forum's avatar
Altera_Forum
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16 years ago

The questions to ask are:

1 - What impedance of cable do you need to use (50ohm, 75ohm, etc.)

2 - What distance (length) do you need to drive.

As an example, The SDI video protocol at 1.5Gbps can perform at over 200 meters on a 75ohm coaxial cable (Belden 1694). SDI uses a scrambled NRZI encoding. In reality, the length is as much or more dependent on the equalizer at the receiving end as it is on the cable driver at the transmitting end. I expect 8b/10b encoding would perform better with regards to length.

Jake