07-01-2021 07:03 AM
I have a vc707 board. I want to send 16 bit data to FMC LVDS pins.
However, I could not find the correct buffer for this task.
Can you recommend and give example usage of an LVDS output buffer.
I tried OBUFDS but it seems it is not the convenient one.
07-01-2021 07:12 AM
Convenient or not, the OBUFDS is the differential output buffer. Look at the language template in Vivado device primitive instantiations. Why is using this buffer inconvenient?
07-02-2021 02:25 AM
Hello Bruce, thanks for the reply.
I don't remember exactly but I read somewhere OBUFDS is not fast enough. Also, I can not select LVDS as I/O std when I use OBUFDS.
I thought there may be a special buffer for LVDS.
07-02-2021 02:42 AM
If your in Vivado,
then the constraints file is normally used to sets the lvds and its type,
then you also have to get the bank voltages correct for it to be placed,
OBUFDS are the standard differential outputs of the FPGA,
how fast do you want to go ?
The "only" faster ones are the Giga bit speed serdes blocks , but they are not LVDS as such.
07-02-2021 05:51 AM
Thank you John. Yes I am using VIVADO. The program used to terminate itself when I tried to select LVDS. I don't remember what I changed but now everything seems OK.