52.8 USB Interface

The USB interface consists of a differential data pair (D+/D-).

Refer to the Electrical Characteristics section for operating voltages which will allow USB operation.

Table 52-8. USB Interface Checklist
Signal NameRecommended Pin ConnectionDescription
D+
  • The impedance of the pair should be matched on the PCB to minimize reflections.
  • USB differential tracks should be routed with the same characteristics (length, width, number of vias, etc.)
  • For a tightly coupled differential pair,the signal routing should be as parallel as possible, with a minimum number of angles and vias.
USB full speed / low speed positive data upstream pin
D-USB full speed / low speed negative data upstream pin
Note: USB Host and Device Interface recommendations can be found in the Basic 32-Bit MCU Design and Troubleshooting Checklist guide on the Microchip web site.