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Transceiver in Cyclone V using less then 614 Mbps

CStoe2
Beginner
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Hi all,

In a recent project I would like to use a camera with a clock of 290 MHz when using Double Data Rate. The throughput rate is therefore 580 Mbps per channel for a total of 10 channels. Now it would be helpful if I could use the transceivers in the Cyclone V for deserialization.

Currently, I use the DDIO IPs, sometimes giving me timing problems. While the design may fits when using multiple seeds, I think using the transceivers might be helpful to avoid problems.

 

The datasheet of the transceivers specifies a minimum data rate of 612 Mbps for the receiver. How does the data rate come about and could I eventually use the transceivers?

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CheePin_C_Intel
Employee
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Hi, As I understand it, you have some inquiries related to the CV transceiver data rate. Yes, you are right, the minimum supported data rate of the CV transceiver is 614Mbps. Your targeted 580Mbps is out of the minimum supported specs. As an alternative, just wonder if you have had a chance to look into LVDS SERDES which should be able to support the specific data rate of yours as well as deserialization factor from 4 to 10. Please let me know if there is any concern. Thank you. Best regards, Chee Pin
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CStoe2
Beginner
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altera-lvds-receiver.PNGHi,

 

thanks for your answer.

The document "Cyclone V Device Interfaces and Integration Document" describes that "the In SDR and DDR modes, the data width from the IOE is 1 and 2 bits, respectively". As a result, the LVDS Reciever does not use the data path with the deserializer for my DDR data input. In my understanding, the design would then be routed just like mine, which uses the DDIO blocks.

 

I have to say that I drive the DDIO IP directly with the clock from the input pin and no intermediate PLL for the data clock. Can this possibly fix the timing issues? I initially tried to use the PLL, but I was overwhelmed by setting the constraints associated with the DDIO block.

 

Best regards,

Christian

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CheePin_C_Intel
Employee
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Hi Christian, Thanks for your update. Regarding the timing issue, I could not comment if the PLL can help to improve your existing timing issue. You may try to see if it is helpful. If it does not help, please feel free to let me know. I will try to see if can duplicate a new case from my side for our timing team to further assist you on closing the timing. Please let me know if there is any concern. Thank you. Best regards, Chee Pin
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CheePin_C_Intel
Employee
476 Views
Hi Christian, Just to follow up with you on this. Thank you.
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CStoe2
Beginner
476 Views

Hi Chee,

 

Finally, I changed the FPGA desgin a bit to get it more stable. Since the data source in this case is a camera, I will successively increase the frame rates and resolutions and check up to which configuration the FPGA design works. I will not use the PLL for now, but keep it in mind. The information that the deserializers do not work for this case answers my primary question. Thanks for the support.

 

Best regards,

Christian

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CheePin_C_Intel
Employee
476 Views
Hi Christian, Glad to hear that you have managed to get your design working. I will set this case to close-pending for now. Thank you.
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