The **MPI4040R4-100-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. --- ### 1. General Specifications Below are the primary technical parameters for this specific part number: | Parameter | Value | | :--- | :--- | | **Inductance** | 10.0 µH | | **Tolerance** | ±20% | | **Current Rating (Irms)** | 3.5 Amperes | | **Saturation Current (Isat)** | 3.8 Amperes | | **DC Resistance (DCR)** | 85 mΩ (Typical) | | **Operating Temperature** | -40°C to +125°C | | **Package / Case** | 4.7mm x 4.06mm (Height: 4.0mm) | --- ### 2. Key Features and Construction * **Molded Construction:** The inductor uses a metal powder core technology. The wire is molded directly into the metal powder, which provides excellent magnetic shielding and reduces EMI (Electromagnetic Interference). * **High Power Density:** Because of the molded design, it offers a very high current handling capability relative to its small physical footprint. * **Soft Saturation:** Unlike ferrite core inductors that lose inductance sharply when current limits are exceeded, the MPI series features "soft saturation," meaning the inductance drops gradually. * **Rugged Design:** The composite core material makes the component resistant to thermal shock and mechanical vibration. --- ### 3. Part Number Breakdown The nomenclature `MPI4040R4-100-R` can be decoded as follows: 1. **MPI:** Series Name (Molded Powder Inductor). 2. **4040:** Physical size (approx. 4.0mm x 4.0mm footprint). 3. **R4:** Height designation (4.0mm maximum height). 4. **100:** Inductance value. The first two digits are significant; the third is the multiplier ($10 \times 10^0 = 10 \mu H$). 5. **-R:** RoHS compliant suffix. --- ### 4. Common Applications Due to its high efficiency and low profile, this inductor is typically used in: * **DC-DC Converters:** Point-of-load (POL) power supplies. * **Portable Electronics:** Tablets, laptops, and handheld devices. * **Battery Powered Systems:** Where high efficiency and low heat generation are critical. * **VRM Modules:** Voltage Regulator Modules for CPUs and GPUs. ---