The **MPI4040R2-3R3-R** is a high-performance, power inductor manufactured by **Eaton (formerly Bussmann)**. It belongs to the MPI (Molded Power Inductor) series, which is characterized by its rugged construction and high current-handling capabilities in a compact footprint. --- ### 1. Key Technical Specifications The part number provides specific details about the component's electrical and physical properties. | Parameter | Specification | | :--- | :--- | | **Inductance** | 3.3 µH | | **Tolerance** | ±20% | | **Current Rating (Irms)** | 3.8 Amperes (Typical) | | **Saturation Current (Isat)** | 5.5 Amperes (Typical) | | **DC Resistance (DCR)** | 48 mΩ (Max) | | **Operating Temperature** | -40°C to +125°C | | **Package Size** | 4.7mm x 4.06mm x 2.0mm (approx.) | --- ### 2. Part Number Breakdown The nomenclature reveals the construction and performance tier: * **MPI**: Molded Power Inductor series. * **4040**: Dimensions (approx. 4.0mm x 4.0mm). * **R2**: Version/Generation (High-current/standard profile). * **3R3**: Resistance/Inductance value (3.3 microhenries). * **-R**: RoHS Compliant. --- ### 3. Core Features & Technology * **Composite Core Material:** It uses a metal flake powder core molded around the winding. This provides a "soft saturation" characteristic, meaning the inductance drops gradually as current increases rather than crashing abruptly. * **Magnetically Shielded:** The molded construction naturally shields the inductor, significantly reducing Electromagnetic Interference (EMI) with neighboring components on the PCB. * **High Power Density:** Designed to handle high current in a very small SMD (Surface Mount Device) package. * **Low Acoustic Noise:** The solid molded structure minimizes vibration (buzzing) often found in traditional wire-wound inductors. --- ### 4. Typical Applications This component is primarily used in power management circuits where space is limited and efficiency is critical: * **DC-DC Converters:** Point-of-load (POL) modules for CPUs and GPUs. * **Mobile Electronics:** Smartphones, tablets, and handheld devices. * **Distributed Power Systems:** Used in telecommunications and server power stages. * **Battery Powered Systems:** Where low DCR is required to preserve battery life. ---