Comprehensive Analysis of Crosstalk Effect at DDR Channel

A typical DDR4 channel includes CPU package substrate, CPU fan-out via, CPU fan-out routing, main bus routing, DIMM fan-in routing, DIMM connector, DIMM board routing, and DARM package. In this paper, the crosstalk impact from each channel element is analyzed. Analysis shows that the CPU fan-out vias and DIMM fan-in vias are more critical to the overall channel crosstalk control, due to the lack of enough return paths or return vias.