HD3SS3220: Route design (length matching) from conn to HD3SS3220RNHT.

Hi Marynard,

If customer has question on routes and high speed layout best practices then I recommended referring to this document: High-Speed Layout Guidelines for Signal Conditioners and USB Hubs.

I will review files and provide some feedback by Monday at the latest. 

Hi Marynard,

Please find the reviewed schematic attached. Layout was difficult to review, can the PCB file be provided? 

Hi Malik

Apologies for the late response. 

Below is the pcb doc .

Regards,

Maynard

Hi,

I will review and get back to you by the end of this week.

Hi Malik,

Thank you for your support. We will be waiting for your update on this.

Though customer have follow-up question regarding the review you have provide. Below is the details.

"

I re-tuned my schematics and now i have to route the ss line.
What should I do with routing after I fix it as you advised?
Should the entire line from the conn to the cap be +-5mil?
(i don't know this region is breakout region or not)
and how about the ss line from cap to HD3SS3220RNHT?

"

Regards,

Maynard

Hi Maynard,

Is the customer asking about the intra-pair skew requirement for routing? if so this requirement is mean to track the entire length from HD3SS3220 to connector. 

Hi Maynard,

In regards to your layout I recommend the following:

• Include GND plane voids under the pads of all passive components in the high speed path.
• Differential routing is good (tightly coupled).
• Consider routing TX and RX paths on bottom layer to eliminate stubs caused by unused copper in the signal vias.
• Route the TX2 and RX1 signals on the bottom layer. I prefer that you use a SMT only USB-C connector to help with SI.
• Lots of vias in the high speed path is a concern (4 sets total, where recommend 2 sets max). Try to eliminate some vias where possible.

You may want to consider using a redriver in this design since high speed signals are going to a connector. Does the connector on this board mount a cable or another PCB?