Arria® 10 Transceiver PHY User Guide

ID 683617
Date 4/01/2024
Public
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

or

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.