Clamping diodes for USB4

Update: August 6, 2023

“Since there are tight budgets on insertion loss and return loss for the USB4 Super Speed lines, Nexperia is offering devices that minimise the impact of ESD protection on the total budget,” said Nexperia product manager Stefan Seider. “By providing two device options, engineers can balance between ESD is protection level by voltage clamping and RF performance.”

  • PESD5V0R1BDSF is optimised for low clamping voltage with ‑0.28dB insertion loss  and ‑19dB return loss at 10GHz
  • PESD5V0R1BCSF is optimised for RF performance with -0.25dB insertion loss and -19.4dB return loss data at 10GHz each. “This makes it ideal for applications with further limited budgets for insertion loss and return loss,” said Nexperia.

Both devices are housed in the low inductance DSN0603-2 (SOD962-2) leadless package, with 0.6 x 0.3mm footprint and 0.3 profile – with return-loss optimized solder pads.

“For USB4, it is mandatory to have ac-coupling Capacitors also for the receiver inputs,” accordign to the company. “The voltage rating of the PESD5V0R1BxSF devices [>2.8 V] allows them to be placed directly behind the connector, which is the preferred position to include these capacitors in the protection and to achieve best system-level ESD performance.”

This voltage rating makes them backwards compatible with all standards that can connect over USB Type-C.  Along with USB4, this includes USB 3.2, older USB3.x, Thunderbolt and HDMI2.1 data lines (in HDMI Alt Mode) – with Thunderbolt up to 40Gbit/s (2 x 20) and HDMI2.1 data up to 48Gbit/s (4 x 12).

This Nexperia page includes more about USB4 protection as well as covering the two PESD5V0R1BxSF devices.