Hello STM Community,
I am developing a custom board based on the MB997E reference design. In this design, the EMIF02-USB03F2 (USB ESD/EMI protection device) is used, but since this part is now obsolete, I am migrating to the USBDF01W5.
I have updated the schematic accordingly (attached). The design also uses:
- STMPS2141STR (USB power switch)
- USBDF01W5 (replacing EMIF02-USB03F2)
- Standard USB connector (475900001)
I would like to request the STM experts and community to please review my schematic connections with focus on:
- Correct integration of USBDF01W5 in place of EMIF02-USB03F2.
- Any impact on EMI/EMC test compliance due to this migration.
- Whether additional filtering (e.g., common-mode choke, RC filters) is required for better EMI performance.
- Placement/grounding recommendations to ensure ESD robustness.
- Review of the series resistors (22 Ω on D+/D– lines) and overall USB signal integrity.
Since EMIF02-USB03F2 included EMI filtering while USBDF01W5 mainly provides ESD protection, I am concerned if this change may cause EMI test compliance issues during certification.
Could you please provide a full review of the circuit and suggest if any modifications are needed to ensure stable operation and successful EMI/EMC test results?
