Return Loss in High-Speed PCB: Causes, S11, and Design Guide
Return loss is one of the most critical signal integrity parameters in modern high-speed PCB design. It directly reflects impedance continuity across transmission lines, vias, connectors, and reference planes. Poor return loss leads to signal reflection, overshoot, undershoot, bit errors, and link instability for PCIe 4.0/5.0, 10G/25G/112G Ethernet, and PAM4 high-rate systems. Understanding return loss…