I am looking at using some resistor arrays or 0201 parts for the line terminations on the DDR3 memory bus. The parts in question are the resistors on page 23 of the EVM. (TI_AM572XEVM_REV_A3a.PDF schematic)
The resistor arrays I am finding are only available in 5% tolerance versus 1% for the 0402 discretes. I am not sure how that would affect performance.
The problem with using 0201 discrete resistors is because the design guide mentions inductance issues with parts smaller than 0402.
And the EVM uses 0402 footprints that are not IPC96 compliant, so we can’t place 0402 parts where they are placed in the EVM design.
We are specing DDR3-1600 (1.25 nS) and DDR3-1866 (1.07 nS) parts but planning to run them at DDR3-1066 (533 MHz) speed. Also the parts will be set to DDR3L voltage levels (1.35V).
My question is which issue would cause more problems for the design? Inductance issues with 0201 parts or tolerance issues with the resistor arrays?
