SLYY200A April   2021  – December 2023 LM25149 , LM25149-Q1 , LM5156-Q1 , LM5157-Q1 , LM53635-Q1 , LM60440-Q1 , LM61460-Q1 , LM61495-Q1 , LMQ62440-Q1 , LMR33630-Q1 , LMS3655-Q1 , TPS55165-Q1 , UCC12040 , UCC12050

 

  1.   1
  2.   Overview
  3.   At a glance
  4.   What is EMI?
  5.   Conventional methods to reduce EMI in the low- and high-frequency ranges
  6.   Innovations in reducing low-frequency emissions
  7.   Spread spectrum
  8.   Active EMI filtering
  9.   Cancellation windings
  10.   Innovations in reducing high-frequency emissions
  11.   HotRod™ package
  12.   Enhanced HotRod QFN
  13.   Integrated input bypass capacitor
  14.   True slew-rate control
  15.   EMI modeling capabilities
  16.   Low-frequency EMI designs using WEBENCH® design tool
  17.   Conducted and radiated EMI results published in data sheets
  18.   Conclusion
  19.   Keep product categories for low EMI

Low-frequency EMI designs using WEBENCH® design tool

The WEBENCH input filter design tool helps you automatically design a proper input filter to mitigate lower-frequency (<30 MHz) conducted EMI noise for compliance standards like CISPR 32 and CISPR 25. The tool optimizes filter size while ensuring that the design complies with a particular standard. It also ensures filter stability and converter-loop stability while designing the filter. This online tool supports over 100 TI power devices.

It is a common mistake to leave an input EMI filter inductor undamped, which negatively affects overall design stability. The WEBENCH design tool performs impedance analysis on the input filter and SMPS (as shown in Figure 24) and suggests the appropriate damping component to ensure stability.

GUID-20231208-SS0I-VQQX-BRNM-3RMX1P5CZ22V-low.gif Figure 24 Input EMI suggestion with impedance analysis in the WEBENCH® design tool.