Electronic – USB 2.0 layout on 2-layer board

Summarizing comment trail as an answer:

The requirement is for a PCB layout for a pass-through between USB2.0 A and B connectors on a PCB. The rest of the circuit on the PCB does not interact with the USB signal path.

Suggested solution:

By changing the physical arrangement of the two sockets to be close together rather than at opposite sides of the board as originally envisaged, the signal trace length and transmission effect concerns are alleviated.

Further, by setting the two connectors at right angles to each other, at one corner of the board area, the need to leave space between them to allow cables to be plugged in, is addressed: The cables would be connected along different edges of the board and would not touch each other.

This allows simplification of routing as well:

• The recommendation for equal length signal paths is inherently addressed
• The arrangement does not interfere with rest of PCB layout, as it is off in a corner
• With the indicated small trace length, transmission line and antenna effects are negligible for USB 2.0 High-Speed transmissions

(as posted by OP).

Concerns that may need addressing:

• Physical robustness of PCB to cope with stresses of repeated cable insertions - A mounting bolt at the corner between the connectors should address this.
• Effective total length of USB cable, adding up the A-side and B-side cables, may exceed USB maximum cable length. The very short PCB section would act merely as an extension of the cable.
• Creative solutions needed for suitably boxing the board with connectors at the corner.

Here are a couple differences between a USB 2.0 host and a USB 2.0 OTG host.

• Support for high and low speed communication are optional for the OTG host
• Support for hubs are optional on the OTG host. If hubs aren't supported then you're limited to only one device on that host.
• Normal hosts are required to be able to supply at least 100mA where as OTG hosts are only required to be able to supply 8mA.
• The OTG host can tun off VBUS.
• OTG uses an AB port that can take both types of USB cable.

You can see a lot the requirements of a conventional USB host are optional on the OTG host. The exact capabilities would depend on how the microcontroller implements it. If the OTG host you pick meets your requirements, there shouldn't be any noticeable difference between the two. On the software side of things, the only difference you should see is the added capability to switch between host and device mode on the OTG part.