The **SCEP147S-R40** is a high-performance, surface-mount (SMD) power inductor typically manufactured by **Signal Transformer** (a division of Bel Fuse) or **Sumida**. It is part of the SCEP147 series, known for its high current handling and low DC resistance. --- ## 1. Technical Specifications The part number follows a specific nomenclature. Here are the primary electronic characteristics for the **R40** variant: | Parameter | Specification | | :--- | :--- | | **Inductance** | 0.40 µH (Microhenries) | | **Tolerance** | ±20% (Standard for this series) | | **Max DCR (DC Resistance)** | Approx. 1.20 mΩ - 1.50 mΩ | | **Saturation Current ($I_{sat}$)** | ~30.0 A - 50.0 A (Depending on temperature rise) | | **Heating Current ($I_{rms}$)** | ~25.0 A - 30.0 A | | **Operating Temperature** | -40°C to +125°C | | **Shielding** | Magnetically Shielded | --- ## 2. Key Component Features ### A. Magnetic Shielding The SCEP147S is a **shielded inductor**. This means the magnetic flux is contained within the component body, which: * Reduces Electro-Magnetic Interference (EMI) with neighboring components. * Allows for high-density PCB layouts. ### B. Core Material It utilizes a **ferrite core** construction. Ferrite is chosen for high-frequency power applications because it offers low core losses, ensuring high efficiency in power conversion. ### C. Low DCR (Direct Current Resistance) The "R40" indicates a very low inductance (0.40µH), which usually correlates to a very thick internal wire or foil. This results in extremely low resistance, minimizing power loss through heat ($P = I^2R$). --- ## 3. Physical Dimensions (Package) The "147" in the part number refers to the physical footprint size: * **Length:** ~15.0 mm * **Width:** ~15.0 mm * **Height:** ~8.0 mm (The "S" suffix often denotes a specific height profile or slightly modified footprint). --- ## 4. Typical Applications Due to its high current saturation and low inductance, the SCEP147S-R40 is used in: 1. **Voltage Regulator Modules (VRMs):** Found on high-end PC motherboards and server CPU power stages. 2. **DC/DC Converters:** High-frequency switching regulators where high efficiency is critical. 3. **Graphic Cards (GPUs):** Handling the high-amperage demands of modern processors. 4. **Renewable Energy:** Small-scale solar inverters or battery management systems. ---