Hi,everyone.
we find this problem when doing layout job of dm365 DDR.
from the TI spec and EVM sch:
DDR_STRBEN is trace to DDR memory
for delay compensation
This net is equal to the DDR_CLKP ( or DDR_CLKN )
plus the length of DDR_DQXX Average Trace length.
But in the EVM spb125 layout board from pectrumdigital.com, the actual length is:
DDR_STRBEN=2128.89+383.08=2511.97Mil.
DDR_CLKP = 1590Mil,
DDR_DQS0 = 1386Mil.
strben = 1590 + 1386 = 2976 mil, But not EQUAL to 2511.97Mil
I am confused. Any body knows why?