ER2J is an advanced software package for high-precision EMI/RFI filtering and suppression. It was developed by Diotec and is used for a wide range of applications including signal integrity, switching power supplies, RF, audio, and video equipment, and much more. It provides a reliable, stable, and cost effective toolset to fine-tune and optimize electromagnetic noise performance, and can provide up to a 200dB reduction in the noise level. The software features an easy-to-use graphical user interface and provides detailed technical analysis to assess a system lead-time and determine the most effective design solutions. It also includes a wide range of simulation tools, statistical process control, and data analysis capabilities.