Schwarzbeck CDN USB 3.0 Coupling Decoupling Network for IEC 61000-4-6

The Schwarzbeck CDN USB 3.0 Coupling Decoupling Network is part of the coupling decoupling network series for conducted common mode immunity testing according to IEC 61000-4-6. The CDN S9 USB 3.0 is compliant to IEC 61000-4-6 figure D.1 and is suitable for immunity testing on screened USB 3.0 lines.

The CDN USB 3.0 is intended to measure EuTs with USB 3.0 interface and for backwards compatibility reasons also for USB 2.0 und USB 1.1 in the frequency range from 150 kHz to 230 MHz. The circuitry is shown in Fig. 3.

All Schwarzbeck CDNs comply to the requirements of IEC 61000-4-6. Each CDN comes with individually measured data and a calibration certificate for the common mode impedance and the voltage division factor. Further typical data for the phase (not normative) can be found in fig. 2.

A variety of calibration adapters and other accessories are available as option. With the two included adapters SA USB in conjunction with the optional series resistor SR100-6W, the required spacing of 30 mm is obtained as depicted in Fig. 9 of IEC 61000-4-6.

The connection to ground can be accomplished using the ground plane of the CDN. Additionally there is a M4 thread located at the AE side to ground as well as a 4 mm socket to connect the device to ground.

Fig. 1: typ. EuT Common Mode Impedance	Fig. 2: Typ. Voltage Division Factor RF-Port to EuT-Port