The **CMT3-6-R** is a high-performance, surface-mount common mode choke designed primarily for EMI (Electromagnetic Interference) filtering in power and signal lines. It is manufactured by **Coiltronics (now part of Eaton)**. --- ## 1. Technical Specifications The following table highlights the core electronic characteristics of the CMT3-6-R: | Parameter | Specification | | :--- | :--- | | **Inductance (Typical)** | 1.3 mH | | **Rated Current (Irms)** | 3.2 Amps | | **DCR (Direct Current Resistance)** | 62 mΩ (max) | | **Operating Temperature** | -40°C to +125°C | | **Mounting Type** | Surface Mount (SMD) | | **Package Size** | Size 3 (Approx. 19.5mm x 16.5mm) | --- ## 2. Key Electronic Features * **Common Mode Noise Suppression:** It is specifically designed to filter out noise that is common to both lines (phase and neutral/positive and negative) while allowing the desired signal to pass. * **Toroidal Core Construction:** Uses a ferrite toroid core which provides high efficiency, low magnetic radiation, and high saturation current. * **Dual Winding:** It features two balanced windings on a single core. The magnetic fields generated by the differential current cancel out, while the magnetic fields from common-mode noise add up, creating high impedance against interference. * **High Current Density:** Despite its compact SMD footprint, it can handle a continuous current of up to 3.2A. --- ## 3. Applications The CMT3-6-R is commonly integrated into the following circuits: 1. **Switch Mode Power Supplies (SMPS):** To prevent high-frequency switching noise from feeding back into the power grid. 2. **DC-DC Converters:** Filtering input and output stages to meet EMC compliance. 3. **Industrial Electronics:** Protecting sensitive control logic from line noise. 4. **Solar Inverters:** Managing common mode currents in high-efficiency energy systems. --- ## 4. Typical Connection Diagram In a standard circuit, the CMT3-6-R is placed between the power source and the load: ```text Line In (+) ----(Winding 1)---- Line Out (+) ) ( ) ( <-- Magnetic Coupling ) ( Line In (-) ----(Winding 2)---- Line Out (-) ```