04-25-2019 02:33 AM
Can anyone recommend a solution to interface GTH Tx to 75 Ohm coaxial cables @12Gbps? And similarly for the other direction. Either using active devices or passive networks.
I have tried SDI and CoaxPress 12G transceivers, but IBERT test does not work over them. I suspect their built-in reclocker function is line encoding sensitive and rejects the pseudo random data used for IBERT test. CoaxPress uses 8B/10B and SDI uses its own scrambling algo.
04-25-2019 02:39 AM
Assuming your looking at SDI video ?
have you looked at the SDI video dirver / receivers ?
04-25-2019 06:12 PM
I had tried Macom and Semtech SDI 12G TX and RX ICs. I could not get IBERT link up with them. I am sure the Macom SDI hardware is working because I can send 12G SDI video over them. I am surprised when I switch to IBERT I can't even get a link up.
Their datasheet mentioned it has built-in reclockers, so I suspect these ICs will detect for SDI standard's own line coding before turning on their outputs
04-26-2019 03:14 AM
Do you have the macom parts with the built in eye checker ?
thats normaly a good start point,
provided the iBert is at the correct clock frequency, why should not the buffers work ?
04-28-2019 06:51 PM
My intent is to use SDI transmitter and receivers to send non-SDI data and to convert GT differential signals to 75 Ohm coax signals. So I use FPGA IBERT as a test to see if these transceivers allows non-SDI signals to pass through.
I believe besides frequency, SDI reclockers are actually line encoding sensitive. I hope someone can confirm/refute this.
04-28-2019 07:06 PM
maybe you can check with Macom and Semtech to see if the PRBS pattern is allowed in the reclockers.
04-28-2019 08:59 PM
Yeah working on that. Meanwhile I am also asking if anyone knows of other solutions.