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Altera_Forum
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11 years ago

Arria II - GX Jitter performance

Hi All, I am using arria II GX : EP2AGX45DF29I3 fpga in my porject. I referred the datasheet of arria II GX and saw the transceiver jitter performances of the GX series fpga's for different pro...
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Altera_Forum
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11 years ago

Hi Alex,

Thank you for the reply. Yes I do find it strange that the company has gone for such an FPGA with a very little information on jitter at such a high data rate. But we have tested the data rate and we are able to achieve about 6.25 Gbps. Unfortunately we are not able to analyse why we are getting such a high jitter. Moreover to measure jitter at such a high data rate we need an expensive oscilloscope.

So that is one of the reason why I asked as to why there is not much information on the jitter specification. However I was able to read about Transmitter specifications for GX and Transmitter REFCLK phase jitter (rms) for 100 MHz REFCLK is 3ps.

REFCLK phase jitter (rms) for 25MHz is 6ps i.e based on the formula provided in the NOTE section by Altera.

Since my refclk is 25Mhz, can this be one of the reason and using a higher freq ref clk can solve my jitter issues??

regards,

Sreeni