Stratix V Device Handbook: Volume 2: Transceivers

ID 683779
Date 11/23/2021
Document Table of Contents

6.8. Transceiver PLL Reconfiguration

You can use the PLL reconfiguration registers to switch the reference clock input to the TX PLL or the clock data recovery (CDR) circuitry.

For example, you can switch the reference clock from 100 MHz to 125 MHz. You can also change the data rate from 2.5 Gbps to 5 Gbps by reconfiguring the transmitter PLL connected to the transceiver channel.

Note: Reference clock switching is only supported on the dedicated REFCLK pin.

The Transceiver Reconfiguration PHY IP provides an Avalon ® -MM user interface to perform PLL reconfiguration.