Greeting Blues Team.
I am working on a custom PCB for Notecard.
Do the lines coming from USB connector to USB_DM and USB_DP need 33 ohm resistors in line?
If not needed…
Is this circuit all I need to cause a PC to enumerate the Notecard as a USB CDC device?
Thanks
Hi Pat,
Yes - your USB VCC, D-, D+, and GND signals are all connected correctly between your USB connector and Notecard M.2 connector to allow Notecard to enumerate and provide a USB Serial interface. You do not need additional inline resistors.
We recommend that you copy the USB shield grounding scheme from our reference Notecarrier designs at GitHub - blues/note-hardware
For instance, here is the relevant section for our Notecarrier-AL schematic:
Thank you John.
I’ll look more at the references.
