Ultra-Fast Common Mode Choke
■ 1.5 mH common-mode inductance at 1 kHz
■ < −40 dB return loss (100 kHz – 200 MHz)
■ Optimized for connecting UFCS series current shunts to oscilloscopes
■ Suitable for use with network analyzers
UFCS-Choke – Ultra-Fast Common Mode Choke
The PMK UFCS-Choke is the companion for PMK’s ultra-fast UFCS current shunts, creating a high-bandwidth measurement path from the shunt directly to a 50 Ω oscilloscope input. Designed for fast switching power electronics, WBG switching-loss analysis, and pulse-current measurements, the combination preserves the signal fidelity of the UFCS shunts while helping to suppress unwanted common-mode currents in ground-referenced test setups.
With more than 4.5 GHz bandwidth as an assembly, 1.5 mH common-mode inductance, and excellent 50 Ω transmission-line performance, the UFCS-Choke captures fast current transients with confidence. Used together with UFCS shunts, it supports precise, low-inductance current measurement while reducing artifacts caused by ground loops and high-speed common-mode disturbances.
For GaN, SiC, and other fast-switching power devices, this PMK solution connects ultra-fast shunt measurements to standard laboratory instruments — where conventional current probes often reach their limits. The UFCS-Choke is not required when the shunt is connected through FireFly®, because that optical isolation already removes ground bounce and ground loops.
Models & Specifications
| Image | Notepad | Article | Bandwidth (−3 dB) | Common-mode inductance | Return loss |
|---|---|---|---|---|---|
UFCS-CHOKE 50 Ohm impedance matched common mode choke, recommended for direct input to oscilloscopes. Includes the SMA(F)-SMA(F) choke, 1 m and 0.5 m SMA(M)-SMA(M) cables, and an SMA(F)-BNC(M) adaptor. | >4.5 GHz (including cables) | 1.5 mH at 1 kHz | < −40 dB (100 kHz – 200 MHz) |
