Hi Experts,
Background:
Customer is using DP83TC813S-Q1 for VCU in vehicle. This is the platform information:
- MCU: R7F702301BFABG-C
- PHY: DP83TC813SRHFRQ1
- 3.3V Power: TPS74633PQWDRBRQ1
The schematic is showed below:
Issue description:
A new batch of PCBA has been patched, and it is normal during debugging after returning to the board. After connecting the car Ethernet converter (100base-T1) with a twisted pair, the impedance matching can be displayed.
The actual code test can also communicate with the PC normally. (Multiple power on and off tests). After a week, re-use the twisted pair to connect to the car Ethernet converter to test the function.
At this time, the impedance does not match. Through the software debugging, it can be read that the connection status is OK (1), But the physical link layer signal quality is 0 (worst case)
Could you comment on this and give customer a few suggestion? Thanks.
Best Regards
Songzhen Guo
