Murata offers numerous noise suppression products EMIFIL (electro-magnetic interference filters) that are designed for use on signal lines and in power supply and general electronic circuits. The EMIFIL product range includes ferrite beads, ferrite cores, common mode chokes and a variety of other components to effectively suppress noise. Three examples include the BLM03BB series, the BLM18SG series and the DLPONS series. The BLM03 ferrite beads are designed to function nearly as a resistor at noise frequencies, which reduces the possibility of resonance and leaves signal wave forms undistorted. The series is effective in circuits without stable ground lines because the BLB series does not need a connection to ground. Its small size (0.6 × 0.3 mm) is suitable for advanced high-density mounting. The BLM18SG series is a surface mount ferrite bead in a 0603 package. It offers low DC resistance, high current capacity and desirable noise suppression. In addition, the series can handle up to 6 A, which helps manufacturers meet FCC regulations regarding noise suppression for high current power lines. It measures 0.8 5 × 0.65 × 0.45 mm. This allows increased high-density mounting capabilities. The series removes unwanted noise without affecting high-speed signal waveforms. The coils achieve this because of increased characteristic impedance (67, 90 and 120Ω) and high coupling (k<= 0.98).
Murata Electronics North America