The pinout of the SN75LVCP422 is such that I'd have to roll the SATA RX pair (through some non-optimal layout) in order to connect RX+/- from the connector to the IC without inverting the bus. Is that correct?
What are the implications of 'inverting' (twice, in, then out) the SATA RX bus through the SN75LVCP422 redriver? I've seen reference design schematics (not from TI) that do just that, as shown:
SATA_Connector Re-Driver SATA_Connector
A+ ------------------------------- >>| R1P T1P | << --------------------------- A+
A- -------------------------------- >>| R1N T1N | << --------------------------- A-
B- -------------------------------- >>| T2P R2P | << --------------------------- B-
B+ -------------------------------->>| T2N R2N | << --------------------------- B+
Is there anything wrong with this?
The pinouts on the 412 parts are such that straight through routing connect more intuitively from connector to IC, but lead times on the 412 part are currently too long to meet our current design cycle.
Regards,
Greg
