Device Family: Arria 10
Type: Answers, KDB Area


Last Modified: September 19, 2017
Version Found: v17.0

Can I use a transceiver RX Pin as a CDR REFCLK for the HDMI Design Example Receiver Interface (Sink) on Arria 10 and Cyclone 10 devices?

Description

No, you cannot use a transceiver RX Pin as a CDR REFCLK for the HDMI™ Design Example Receiver Interface (Sink) on Arria© 10 and Cyclone© 10 devices.

The HDMI TMDS_CLK frequency is dependent on the video resolution. Low resolutions have a TMDS_CLK frequency of 27MHz which is below the minimum CDR REFCLK frequency. The HDMI Design Example implements a cascaded IOPLL architecture to multiply-up the TMDS_CLK for low resolution video.

TMDS_CLK -> IOPLL -> CDR REFCLK

The RX Pin as a REFCLK feature can only be used when connected directly to the CDR REFCLK. Your design will fail to fit in the Quartus© Prime software if you place the HDMI Design Example RX REFCLK on an Rx Pin.

To work around this problem you should place your HDMI Design Example TMDS_CLK on a dedicated transceiver REFCLK pin.