AN 952: Intel® Arria® 10 and Intel® Stratix® 10 HDMI 2.1 System Design Guidelines

ID 709310
Date 6/21/2022
Public

4.3.1. FPGA TX Settings

Intel recommends the settings in Table 6 for your FPGA TX. Both FPLL and ATXPLL apply. In general, ATX PLL has a slightly better margin than FPLL, although this may not be a dominant factor for Intel® Arria® 10 and Intel® Stratix® 10.

For a complete list of settings, refer to Transceiver User Guide.

Table 6.  FPGA TX Recommended Settings
Item Value
Vod output swing ctrl 30
Pre emp sign 1st post tap Fir post 1t neg
Pre emp sign 2nd post tap Fir post 2t neg
Pre emp switching ctrl 1st post tap 5
Pre emp switching ctrl 2nd post tap 0
Pre emp sign pre tap 1t Fir pre 1t post
Pre emp sign pre tap 2t Fir pre 2t neg
Pre emp switching ctrl pre tap 1t 0
Pre emp switching ctrl pre tap 2t 0
Slew rate ctrl Slew r5

Set TX slew rate to r5 to ensure all four TMDS data channels (three data channels and one clock) are within the 2 UI bonding requirements of Test Point 1 (TP1) and meet inter-lane skew requirements.

Your TX redriver settings are determined by your PCB design profile. Intel recommends a minimum VOD setting of 1.0 on the TX redriver.