6.1.2. LVDS SERDES Circuitry
The Stratix® V devices have built-in serializer/deserializer (SERDES) circuitry that supports high-speed LVDS interfaces. You can configure the SERDES circuitry to support source-synchronous communication protocols such as RapidIO®, XSBI, serial peripheral interface (SPI), and asynchronous protocols such as Gigabit Ethernet (GbE) and SGMII.
The following figure shows a transmitter and receiver block diagram for the LVDS SERDES circuitry with the interface signals of the transmitter and receiver data paths.
The preceding figure shows a shared PLL between the transmitter and receiver. If the transmitter and receiver do not share the same PLL, you require two fractional PLLs. In single data rate (SDR) and double data rate (DDR) modes, the data width is 1 and 2 bits, respectively.
The ALTLVDS transmitter and receiver requires various clock and load enable signals from a fractional PLL. The Intel® Quartus® Prime software configures the PLL settings automatically. The software is also responsible for generating the various clock and load enable signals based on the input reference clock and selected data rate.