GTS Transceiver PHY User Guide: Agilex™ 3 FPGAs and SoCs

ID 848344
Date 8/04/2025
Public
Document Table of Contents

3.3.5.1. PMA Configuration Rules for SDI Mode

You can implement the SDI protocol mode with the GTS PMA/FEC Direct PHY IP by following the steps shown below:
  1. In the Common Datapath Options select SDI for the PMA configuration rules setting.
  2. Configure the data rate to match the specific SDI standard you are using.
  3. Ensure that the reference clock is set to correct frequency to support the SDI data rate.
  4. Configure the clock dividers to match the SDI data rate.
The following configurations are supported in SDI mode.
Table 26.  Configurations Supported in SDI Mode
Configuration Data Rate (Mbps) Refclk Frequencies (MHz) PMA Data Width
HD-SDI 1,485 74.25, 148.5 20-bit
1,4835 74.175, 148.35 20-bit
3G-SDI 2,970 148.5, 297 20-bit
2,967 148.35, 296.7 20-bit
6G-SDI 5,940 297, 594 20-bit
12G-SDI 11,880 297, 594 20-bit
If you are implementing the SDI mode, the following are important implementation details:
  • Non-bonded mode for SDI: The mode does not use bonded lanes because it transmits video, audio, and data over a single channel, making multi-lane bonding unnecessary.
  • RX AC cap bypass: The RX AC coupling on-chip capacitor is bypassed to ensure the receiver can handle the SDI signal's DC components, improving signal quality and reducing distortion. Refer to Receiver Buffer and Equalizer for more information.
  • TX PLL fractional mode: If you are implementing parallel loopback without a VCXO, the TX PLL operates in fractional mode with a reference clock frequency of 141 MHz to generate precise clock frequencies needed for accurate data transmission. Refer to TX Datapath Options Parameters for more information on the fractional mode.

You can implement the SDI mode configuration using the GTS PMA/FEC Direct PHY IP and combine it with the GTS SDI II IP, which provides the upper layer protocol implementation, for a complete solution of the SDI protocol. Refer to the GTS SDI II IP Design Example User Guide for more details.

This SDI selection also enables you to implement the dual simplex mode for the GTS PMA/FEC Direct PHY IP. Refer to the GTS Transceiver Dual Simplex Interfaces User Guide for details on how to implement the dual simplex mode.