Other Parts Discussed in Thread: TUSB1210
My customer found the TUSB1210EVM schematic should have an error, and the EVM based board design caused a power supply issue. Could you please check?
When evaluating the prototype based on EVM schematic, my customer found that VBAT is approx. 2V and unstable. This caused register access error from ULPI.
EVM schematic has a net which VBAT - VDD33 - VDD3P3_A are tied together and not connected to other power supply.
However, my customer found that the net is tied to BOARD_3P3V from the actual EVM measurement.
So, it can be concluded that the EVM error caused the power supply issue.
Please find the internal link here for the schematic. (Please connect to VPN for download)
From the above, please support the requests below:
- Could you please provide the right EVM schematic?
- My customer confirmed that connecting external 3.3V power source to VBAT - VDD33 - VDD3P3_A net resolves the issue on the customer board. Is this the right resolution?
- My customer has TUSB1210 x2 on the same board. Is it OK to tie VBAT and VDD33 of both chip together to the system 3.3V supply?