1. Agilex™ 5 LVDS SERDES Overview
2. Agilex™ 5 LVDS SERDES Architecture
3. Agilex™ 5 LVDS SERDES Transmitter
4. Agilex™ 5 LVDS SERDES Receiver
5. Agilex™ 5 High-Speed LVDS I/O Implementation Guide
6. Agilex™ 5 LVDS SERDES Timing
7. LVDS SERDES FPGA IP Design Examples
8. Agilex™ 5 LVDS SERDES Design Guidelines
9. Agilex™ 5 LVDS SERDES Troubleshooting Guidelines
10. LVDS SERDES User Guide: Agilex™ 5 FPGAs and SoCs Archives
11. Document Revision History for the LVDS SERDES User Guide: Agilex™ 5 FPGAs and SoCs
8.1. Use PLLs in Integer PLL Mode for LVDS SERDES
8.2. Use High-Speed Clock from PLL to Clock SERDES Only
8.3. Pin Placement for Differential Channels
8.4. SERDES Pin Pairs for Soft-CDR Mode
8.5. Placing LVDS SERDES Transmitters and Receivers with External PLL
8.6. Sharing LVDS SERDES I/O Lane with Other IPs
4.2. Clocking the LVDS SERDES Receivers
The I/O PLL receives the external clock input and generates different phases of the same clock. The DPA block automatically selects one of the clocks from the I/O PLL and aligns the incoming data on each channel.
The synchronizer circuit compensates for any phase difference between the DPA clock and the data realignment block. When necessary, the data realignment circuitry, which you control, inserts a single or multiple bits of latency in the serial bit stream to align the data to the word boundary.
The physical medium connecting the transmitter and receiver SERDES channels may introduce skew between the serial data and the source-synchronous clock. The instantaneous skew between each SERDES channel and the clock also varies with the jitter on the data and clock signals as seen by the receiver.
The different modes provide different options to compensate the skew between the source synchronous or reference clock, and the serial data:
- Non-DPA mode—you can statically select the optimal phase between the source synchronous clock and the received serial data.
- DPA mode—the DPA circuitry automatically selects the best phase between the source synchronous clock and the received serial data.
- Soft-CDR mode—provides opportunities for synchronous and asynchronous applications for chip-to-chip and short reach board-to-board applications for SGMII protocols.
Note: Only the non-DPA mode requires manual skew adjustment.