## Overview of the ESD-R-22SD The **ESD-R-22SD** is a high-performance, snap-on EMI (Electromagnetic Interference) core manufactured by **KEMET**. It belongs to the ESD-R series, specifically designed for round cables to suppress high-frequency noise and prevent electrostatic discharge (ESD) related failures. --- ### 1. Key Technical Specifications The part is characterized by its physical dimensions and its magnetic properties. | Feature | Specification | | :--- | :--- | | **Material** | Mn-Zn (Manganese-Zinc) | | **Shape** | Round / Toroidal Core | | **Inner Diameter (ID)** | ~11.0 mm | | **Outer Diameter (OD)** | ~22.0 mm | | **Height (H)** | ~15.0 mm | | **Frequency Range** | High-frequency suppression (MHz range) | | **Coating** | Polyamide Resin (UL94 V-2) | --- ### 2. Functional Components The ESD-R-22SD consists of two primary functional parts: * **Ferrite Core:** The internal magnetic component made of Mn-Zn. This material is chosen for its high permeability, allowing it to absorb electromagnetic noise and convert it into a negligible amount of heat. * **Case / Enclosure:** A protective plastic shell that holds the ferrite ring. The "SD" designation often refers to a specific casing style or dimension variant intended for easy integration onto existing wiring. --- ### 3. Applications and Usage This part is typically used in environments where electronic signals are sensitive to external noise or where the device itself emits interference. * **Computer Peripherals:** Used on USB, HDMI, or power cables to prevent data corruption. * **Consumer Electronics:** Found in TVs and audio equipment to maintain signal integrity. * **Industrial Equipment:** Protects sensors and control lines from electrical "noise" generated by heavy machinery. * **EMI Countermeasures:** Used during the prototyping phase to pass EMC (Electromagnetic Compatibility) testing without redesigning the PCB. --- ### 4. Installation Mechanism The ESD-R series is designed for versatility: 1. **Threading:** The cable is passed through the center of the ring. 2. **Multiple Turns:** For increased impedance (better noise filtering), the cable can be looped through the core multiple times. 3. **Positioning:** For maximum effectiveness, the core should be placed as close to the noise source or the entry point of the device as possible. ---