EMI filters reduce differential mode conducted emissions for switching power supplies

TDK Corporation has introduced the TDK-Lambda RGF board-mount EMI filters. Suitable for power supplies with high input current requirements, these 20 and 40A filters are designed to deliver outstanding differential mode filtering. Utilising advanced TDK component technology, these modules streamline system-level compliance with CISPR and other relevant standards.

The RGF filters are encapsulated for protection in harsh environments, measure 52.8mm x 35.2mm x 12.7mm in size and feature a robust five-sided metal case. The design features two threaded and two non-threaded mounting holes, ensuring easy installation and enhanced cooling in both conduction- and convection-cooled systems. Applications include harsh industrial, COTS, test and measurement, communications, broadcast, and robotics.

When used in conjunction with non-isolated DC-DC converter modules, the filters supply a significant amount of differential mode attenuation over a wide frequency range. This lowers overall system noise and simplifies compliance with typical EMI standards. The input voltage ranges from 0V to 80V and withstands input transients of up to 100V for 100ms durations.

The operating case temperature is between -40C to +120C, with a qualified Thermal Cycling Test (TCT) of 700 cycles, or -40C to +125C with a 60C/minute ramp, and a 30-minute dwell time. The filters are compliant with MIL-STD-810G 516.6 Procedure I and IV for shock and MIL-STD-810G 514.6 Procedure I, Cat 10 for vibration.