The **MPI4040R4-R33-R** is a high-performance, power inductor manufactured by **Eaton (formerly Coiltronics)**. It belongs to the MPI (Molded Powder Inductor) series, which is specifically designed for high-current applications where space is limited. --- ### ## Technical Specifications The part number defines the electrical characteristics and physical dimensions of the component. | Parameter | Specification | | :--- | :--- | | **Inductance** | 0.33 µH (Microhenries) | | **Tolerance** | ±20% | | **DCR (Direct Current Resistance)** | 4.4 mΩ (Typical) | | **Rated Current (Isat)** | 22 A (Saturation Current) | | **Rated Current (Irms)** | 14 A (Temperature Rise Current) | | **Operating Temperature** | -40°C to +125°C | | **Package Size** | 4.7mm x 4.06mm x 4.0mm | --- ### ### Key Features and Construction 1. **Molded Construction**: The inductor is made using a metal powder molding process. This provides a rugged, magnetically shielded structure that minimizes electromagnetic interference (EMI). 2. **Soft Saturation**: Unlike ferrite core inductors that lose inductance sharply when current increases, the MPI series has a "soft saturation" curve. This makes it more stable in variable load conditions. 3. **High Power Density**: It offers one of the highest current ratings relative to its small footprint (4040 case size). 4. **Low DCR**: The low internal resistance reduces power loss and heat generation, increasing the overall efficiency of the power circuit. --- ### ### Typical Applications This component is primarily used in DC-DC converters and power management modules (VRMs). Common devices include: * **Computing**: Laptops, servers, and high-end graphics cards. * **Networking**: High-speed routers and switches. * **Portable Electronics**: Handheld medical devices and tablets. * **Automotive**: Infotainment systems and LED lighting drivers. --- ### ### Part Number Breakdown * **MPI**: Series Name (Molded Powder Inductor) * **4040**: Dimensions (approx. 4.0mm x 4.0mm) * **R4**: Height code (approx. 4.0mm) * **R33**: Inductance value (R represents the decimal point: 0.33µH) * **-R**: RoHS compliant