How to correctly wire the TVS diodes for differential signals in a data center switch?

The wiring method of the TVS diodes for differential signals in data center switches determines the protection effect. The correct solution is to connect a bidirectional TVS diode, such as the EASTEC LC3V3D3B (VRWM=3.3V, junction capacitance 1.2pF) from EASTEC, across the differential pairs, i.e., wire-to-wire protection instead of wire-to-ground. This connection utilizes the center tap of the transformer secondary winding to ground through a Bob-Smith circuit to form a common-mode discharge path. The wire-to-wire connection can simultaneously suppress differential-mode ESD and surges, and the clamping voltage symmetry error is <5%, avoiding common-mode to differential-mode noise. In actual measurements, the wire-to-ground connection has a residual voltage of 42V at ±8kV ESD, while the wire-to-wire connection has a residual voltage of 28V, reducing eye diagram jitter by 15ps. The PCB layout must ensure that the TVS differential pin length error is <10mil.