Team,
We have a question regarding usage of coax cables in FPD-Link III communication with DS90UB949-Q1.
Fig. 29 in datasheet (SNLS452) shows application with coax cable, and it shows that there is one coax per link. On the other hand, on the DS90UB949-Q1 Evaluation Module there are two coax connectors per link shown on page 39 (SNLU169). It is confusing why positive and negative output of one lane are both connected with its own coax connector? It seems like each of them need to be connected via separate coax cable to the other side (deserializer), which is not according to datasheet (SNLS452).
In document "What you need to know about high-speed cables for FPD-Link III SerDes" (SLYT726) the usage of coax cable is according to datasheet (SNLS452), and it seems that there is no significant difference in using coax cables vs. STP. But in datasheet (SNLS452) in "High Speed Interconnect Guidelines" it is recommended to use 100Ohm coupled differential pairs.
The question is: is there any advantage of using STP or is it possible to use coax cable for FPD-Link III as it is shown in datasheet (SNLS452) to get the same level of performance?
Thanks for your help.
TI Customer
