1GHz choke for automotive power over coax

April 13, 2017 // By Nick Flaherty
TDK  ADL3225V choke PoC coax
TDK has launched a wire wound choke inductor for automotive power over coax (PoC) applications with a 1GHz bandwidth.

The ADL3225V has a DC resistance of 0.9 Ω with high impedance over a broad frequency spectrum of 1 MHz up to 1 GHz. The new design offers good DC superimposition characteristics for separating the power from the signal path such as separating the signals of sensors and cameras that are connected via automotive Ethernet. The rated inductance of the choke is 47 µH and the rated current (Isat) is 300 mA.

PoC applications require high impedance at the branch of the power line and the signal line in order to prevent the high-frequency signal from causing interference on the power line with its low load impedance. TDK's proprietary structural design and winding combined with the fully automated manufacturing process ensures the excellent electrical properties and high reliability of the new inductors.

The growing number of sensors and cameras in cars is driving the need to speed up the communications between the many ECUs (electric control unit). Advanced communication protocols such as automotive Ethernet with a data rate of up to 100 Mbit/s and low-voltage differential signaling (LVDS) with a transmission rate of up to 1.5 Gbit/s) are both being used for the image signals from on-board camera to the main circuit board. PoC, in which both the data and power are transmitted simultaneously over the same coaxial cable, serves to reduce the weight of wire harnesses and improve fuel consumption.

In the future, TDK will further expand the lineup with more compact types and higher operating temperatures for a wider range of automotive applications.

The choke is qualified to AEC-Q200 and measures 3.2 mm x 2.5 mm x 2.4 mm. Mass production is scheduled to begin in April 2017.


Related stories: