Analysis of Echo and Crosstalk Cancellation in Simultaneous Bidirectional Transceivers for Dense Die-to-Die Interconnects

The impact of echo and crosstalk cancellation in die-to-die interconnect links that employ simultaneous bidirectional (SBD) signaling is analyzed in the context of a 24-wire transceiver operating over a four-layer interposer. Simulation results show that these techniques allow for a 4-rank transceiver system with $40\mu m$ bump pitch to occupy only $240\mu m$ die edge width and signal up to 128Gb/s per data channel wire over a very tight $4\mu m$ signal-to-signal pitch, resulting in a 46.9Tb/s/mm edge density. The proposed crosstalk cancellation circuitry improves the inbound signal voltage margin at 32GHz by 22% at a $\text{BER} =10^{-12}$.