Arria® 10 Transceiver PHY User Guide

ID 683617
Date 4/01/2024
Document Table of Contents

2.4.12. Unused Transceiver RX Channels

To prevent performance degradation of unused transceiver RX channels over time, the following assignments must be added to an Arria® 10 device QSF. You can either use a global assignment or per-pin assignments.

set_global_assignment -name PRESERVE_UNUSED_XCVR_CHANNEL ON


set_instance_assignment -name PRESERVE_UNUSED_XCVR_CHANNEL ON -to <pin_name (U34, for example)>

An example of a <pin_name> is U34, not PIN_U34.

When you perform this procedure, the Quartus® Prime software instantiates the clock data recovery (CDR) PLL corresponding to each unused receiver channel. The CDR uses CLKUSR as reference clock and is configured to run at 1 Gbps. To use CLKUSR as reference clock, the pin must be assigned a 100- to 125 MHz clock. When you implement these assignments, it causes a power consumption increase per receiver channel. Please contact your local support center for details.