74279408 – WURTH

Overview

The Wurth Elektronik 74279408 is a single-channel common mode choke designed for effective EMI suppression in signal and power lines. Its primary function is to attenuate differential mode noise while allowing the desired signal to pass, achieving a significant impedance of 3 kOhms at its rated frequency. A critical design consideration when selecting this WE-ZB series choke is the relatively wide inductance tolerance of 35%; engineers must account for this variability in their filtering calculations, particularly in sensitive high-speed data applications where precise impedance matching is paramount for signal integrity.

Key Features

• Inductance: 100 µH
• Impedance: 3 kΩ (typical)
• Maximum DC Current: 500 mA
• Maximum DC Resistance: 170 mΩ
• Operating Temperature Range: -40°C to +85°C
• Dimensions: 8 mm (L) x 3.5 mm (W) x 9.5 mm (H)

Applications

The component is engineered for deployment in systems requiring high reliability and performance under specific operating conditions. It provides functional stability across the stated design envelope.

• Suppression of common mode noise in USB 2.0 data lines
• EMI filtering for DC power supplies in industrial controls
• Noise reduction in audio signal paths
• Line filtering for communication interfaces (e.g., RS-232)