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Altera_Forum
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12 years ago

Cyclone V LVDS differential termination and RZQ

Hello, I am designing a board with differential LVDS interfaces (receive). I want to use the internal differential termination Rd and the manual is not very explicit on whether the RZQ resistor ha...
Altera_Forum's avatar
Altera_Forum
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12 years ago

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I don't agree. The device manual is quite clear about the fact that Rd on-chip-termination for LVDS inputs doesn't use calibration - and thus doesn't depend on RZQ.

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Hello, well if you can point out where in the manual it is stated as clearly as you write it in your reply, I may

have missed it. The manual talks about RZQ and Rs,Rt, but never mention that Rd is not concerned. It also implies that Rd does not track PVT variations then.

Anyway, I ended to this conclusion, and having your advice helps solving this uncertainty (at least for

me). Thank you.

Pascal