Common-Mode Filters with ESD Protection for High-Speed Serial Interfaces

Published  May 24, 2022   0
Common-Mode Filters with ESD Protection

STMicroelectronics has introduced new common-mode filters that have an extremely wide differential bandwidth of 10.7GHz and are designed to protect antenna sensitivity in adjacent wireless circuitry from the latest serial digital interfaces. The 2-channel ECMF2-40A100N10 and 4-channel ECMF4-40A100N10 common-mode filters are compatible with high-speed interface standards including USB 3.2 Gen 2, USB4, HDMI 2.1, and DisplayPort.

Both filters are housed in compact micro quad flat no-lead (µQFN) packages only 0.5mm high and are suited to demanding industrial applications as well as consumer products. They are well suited to protect smart factory equipment, imaging systems, medical devices, laboratory equipment, home-automation systems, set-top boxes, smart televisions, game consoles, notebooks, tablets, and docking stations.

With their low serial resistance of just 3Ω, which minimizes eye-diagram distortion, these filters preserve signal integrity. These filters deliver deep common-mode attenuation (Scc21) from 2.4GHz to 7GHz, reaching -21dB at 5GHz, and effectively prevent interference with Wi-Fi and Bluetooth receivers. In addition to tackling antenna desensitivity issues, the filters can be used for general interface-noise reduction to ensure compliance with electromagnetic compatibility (EMC) regulations.

Key Features

  • 10.7 GHz differential bandwidth to comply with HDMI 2.1, HDMI 2.0, HDMI 1.4, USB4, USB 3.2 Gen2, USB 2.0, MIPI, Display port 2.0, etc.

  • High common mode attenuation on WLAN frequencies Low serial resistance: 3.0 Ω

  • Very low PCB space consumption

  • Thin package: 0.5 mm max.

  • High reduction of parasitic elements through integration

  • Lead free and RoHS package

  • Exceeds IEC 61000-4-2 level 4 standard

The ECMF2-40A100N6 in 1.35mm x 1.4mm 6-lead µQFN-6L and ECMF4-40A100N10 in 1.35mm x 2.2mm 10-lead µQFN-10L are now in production. Pricing starts from $0.19 for the ECMF2-40A100N10 and $0.26 for the ECMF4-40A100N10, for orders of 1000 pieces.