Common-mode filters protect automotive circuits
Automotive-qualified, common mode filters (CMFs) from STMicroelectronics protect interface ICs in high speed serial buses.
The ECMF04-4HSM10Y and ECMF04-4HSWM10Y integrate transient-suppression diodes with low clamping voltage.
They are claimed to be the first CMFs on the market with automotive-grade qualification and automotive surge compliance guaranteed. In addition to being produced and qualified according to AEC-Q101 requirements, they are also designed and tested against automotive surge specifics such as ISO10605.
The ECMF04-4HSM10Y and ECMF04-4HSWM10Y filters replace discrete common-mode chokes or LTCC (low-temperature co-fired ceramic) devices that are typically larger and provide no ESD protection. They are positioned on high-speed data lines for camera, radar, display, multimedia and other connections to prevent interference with wireless-communication equipment in advanced driver assistance systems (ADAS). The devices have a footprint of 3.5mm2, and 0.75mm high to save board space, simplify design, and lower bill of materials costs in space- and cost-sensitive applications.
The ECMF04-4HSM10Y has 2.2GHz differential bandwidth to suppress common-mode noise on HDMI 1.4, MIPI, and connections. Attenuation, reaching -25dB at 900MHz and -14dB at 1.5GHz, prevents radiated noise from reducing the sensitivity of cellular and GPS antennae.
The ECMF04-4HSWM10Y has a wider 3.5GHz bandwidth and extends the application range to LVDS, DisplayPort, USB 3.1, and HDMI 2.0 buses. It offers -30dB attenuation at 2.4GHz and -16dB at 5.0GHz, ensuring it protects Bluetooth equipment and vehicle to everything (V2X) Wi-Fi antennae, as well as cellular and GPS systems.
The ECMF04-4HSM10Y and ECMF04-4HSWM10Y are in production now, in 2.6mm x 1.35mm QFN10L packages.