The **SS20H-R04450** is a common mode choke coil (inductor) typically manufactured by companies like **KEMET** (NEC TOKIN). It is designed primarily for noise suppression in power supply circuits. --- ### ## Technical Specifications The part number defines the physical and electrical characteristics of the component. | Parameter | Value / Description | | :--- | :--- | | **Series** | SS20H (High permeability core) | | **Rated Current** | 0.4 A (400 mA) | | **Inductance (min)** | 45.0 mH | | **Rated Voltage** | 250 VAC | | **DC Resistance (max)** | 2.10 $\Omega$ per line | | **Operating Temperature** | -25°C to +120°C | | **Mounting Type** | Through-Hole (THT) | --- ### ### Key Electronic Components & Features #### 1. Ferrite Core The "SS" series uses a high-permeability manganese-zinc (Mn-Zn) ferrite core. This material is optimized to provide high impedance at lower frequencies, making it effective at filtering electromagnetic interference (EMI). #### 2. Dual Winding Structure The component consists of two separate copper wire coils wound onto a single core. * **Common Mode Suppression:** It allows differential signals (the power you want) to pass while creating high impedance for common-mode noise (unwanted interference occurring on both lines). * **Safety Spacing:** The "H" in the series name often denotes a vertical configuration, which saves PCB real estate. #### 3. Insulation & Safety * **Dielectric Strength:** Designed to withstand 2,000 VAC for one minute between lines. * **Insulation Resistance:** Typically rated at 100 M$\Omega$ minimum at 500 VDC. --- ### ### Common Applications This specific part is widely used in AC/DC power supplies for consumer electronics where low current (0.4A) and high noise suppression (45mH) are required. * **Switch-Mode Power Supplies (SMPS):** To prevent high-frequency switching noise from entering the power grid. * **LED Lighting Drivers:** To comply with EMI regulations. * **Office Automation:** Used in printers and scanners. * **Home Appliances:** Filtering noise in smart home devices. --- ### ### Typical Circuit Representation In a standard schematic, the SS20H-R04450 is placed immediately after the AC input and fuse, but before the bridge rectifier. ```text AC Line In ----(Coil 1)---- Rectifier (+) AC Neut In ----(Coil 2)---- Rectifier (-) ^ (Common Mode Choke) ```