Demo: Signal Integrity Products for USB Type-C with DP Alt-Mode Active Cable Applications
Hi everybody my name is Limas Lin. Today, I would like to demonstrate to you our active redriver chip for USB Type-C solutions.
We have seen the resolution of the TV display go from 1080p all the way to 4K, and now it is heading for 8K. Currently, you can see many different technologies or interfaces try to reach the 4K and 8K arena. You can use the HDMI DisplayPort™ or Thunderbolt™ in USB 3.1.
USB 3.1 is a new technology that everybody is adapting. Today it supports USB2, USB 3.1, and 10Gb SERDES, and it will also support alternatives like DisplayPort, Thunderbolt or MHL.
All these technologies can be integrated into one single connector, even providing the power supply and power delivery. As this resolution goes higher, the speed increases and your cable reach reduces drastically, and that's a problem for the user experience.
According to USB 3.1 Type-C standard, the 10Gb can only be sustained for 1m of the cable distance, which is not convenient for a lot of applications, especially for the DisplayPort or the MHL for the 4K display. You might have a projector on the top of the ceiling. You might have a big screen TV, which is much more than 1m distance from you. So, Renesas does have the technology, called de-emphasis and equalizer, to extend the distance of this thin cable to add 5m - 10m and still achieve the 10Gb speed.
So now I'd like to show you a live demo of this 4K system that we have prepared right here. As you can see, we have a 4K-capable desktop PC with DisplayPort output, and we have a Dell 4K monitor right here. Now I will use the 2m DisplayPort-to-DisplayPort cable to demonstrate the working system of 4K video transmitting from the source to the device on the monitor here. Once I connect the cable with just 2m distance, the 4K signal will display on the monitor. This screen shows you the 4K 60Hz full refresh rate and the resolution.
Now, I'd like to show you what will happen with a 5m passive cable. Here we have prepared a passive 5m Type-C-to-Type-C cable as I'm going to show you right here. Basically, we just wired the Type-C head to a 5m, 34 gauge cable, and we made some DisplayPort-to-Type-C converters on the source side and the Type-C-to-DisplayPort converter on the device side. I will connect this 5m cable from the source to the device now. As you can see, after the 5m signal degraded too much the monitor does not have any display, so this is not a good user experience.
With the Renesas technology, we actually enhance the signal on the source side and equalize the cable loss using our advanced equalizer technology. At both ends, we have our equalizer and de-emphasis chips on this exact same 5m cable. We have an ISL35411 on the source end to de-emphasize the signal and then on the other side we have ISL36411 to equalize the cable loss. On both ends, we have active devices to make sure that the 4K signal will be able to pass through the high speed of the DisplayPort signals.
Let me demonstrate to you on the working system here. So we have built a DisplayPort-to-Type-C converter on the source side, now let me connect the source side and then connect this cable source right here. On the device side, display side, we also have a converter from Type-C to-DP (DisplayPort). So, this is the working 4K screen you can see right here. This concludes our demonstration for today. Basically, you can see the 5m long cable does not work, but with our active redriving capability, we are able to make the system work.
Besides this Type-C with DP technology, we also have various eval boards/references design kits for the customer. For more information on those reference design kits, please contact our technical support teams and thank you for watching today's demo.