Should data center switches be grounded at a single point or at multiple points?

The grounding strategy for data center switch PCBs needs to be selected based on frequency: low frequencies (<1MHz) use single-point grounding to avoid ground loops, while high frequencies (>10MHz) use multi-point grounding to reduce ground impedance. Switch digital circuits operating at frequencies >100MHz must use multi-point grounding, meaning the ground plane is treated as a complete reference plane without segmentation, and all signal vias are grounded vias for return current. The chassis ground is connected to the signal ground at a single point in the I/O interface area via a high-voltage capacitor. Audiotech recommends the following PCB stack-up: 8-layer board TOP-GND-S1-PWR-S2-GND-BOT, ensuring complete ground planes on adjacent layers, with grounding via spacing ≤λ/20. Actual measurements show that multi-point grounding results in 8-12dB lower radiated emissions compared to single-point grounding.