LVDS Transmitter and Receiver in Stratix II

[Altera_Forum]

hi all, 

i am designing a board using stratix II FPGA (EP2S15F484C3).. I want to know whether this FPGA has the inbuilt lvds transmitter and receiver or i have to use external lvds transmitter and receiver ICs.   please help me...      regards Asha

[Altera_Forum]

It has internal transmitters. Higher data rates can be achieved only with internal LVDS interface, also you can expect higher immunity against on-board generated interferences. If external transmitters/receivers are required for some reason, you should use differential LVDS repeater chips rather than interfacing the FPGA singled-ended. 

 You should pay attention however to the I/O-voltage and pin placement requirements when using LVDS. The Quartus Pin Planner helps to keep all constraints.

[Altera_Forum]

hi... 

thanks for the reply....   ya, i will take care of the I/O-voltage and pin placement requirements for using LVDS.   i want to know, if i want to use the LVDS transmitter and receiver inbuilt in FPGA, how do i instantiate them. Is there any megafunction available or how it is done?

[Altera_Forum]

Normally, you instantiate a LVDS transmitter or receiver by assigning LVDSI/O standard to a single ended port pin with an optional DIFFIO_xxp function. The inverted DIFFIO_xxn is then selected by the Quartus fitter automaticly. There's are also differential I/O low-level primitives, but they are rarely required in standard designs.

[Altera_Forum]

hi.... thanks for the reply 

"you instantiate a LVDS transmitter or receiver by assigning LVDSI/O standard to a single ended port pin with an optional DIFFIO_xxp function"  This means in the pin assignment editor we just have to change the I/O standard.... we need not have to instantiate the altlvds receiver/ transmitter megafunction.

[Altera_Forum]

The LVDS Megafunction is providing the serializer/deserializer. In most applications of LVDS I/O standard, it will be used. But it's not required to use the I/O standard.