## Analysis of the SD20-R47 Electronic Component The **SD20-R47** is a surface-mount (SMD), high-power, shielded inductor typically manufactured by **Eaton (formerly Cooper Bussmann)**. It belongs to the **SD20 Series**, designed for high power density and space-constrained applications. --- ### 1. Key Technical Specifications The part number "R47" specifically refers to the inductance value. Below are the primary technical parameters: | Parameter | Specification | | :--- | :--- | | **Inductance** | 0.47 µH | | **Tolerance** | ±20% | | **Current Rating (Irms)** | ~4.48 Amps | | **Saturation Current (Isat)** | ~6.00 Amps | | **DC Resistance (DCR)** | ~15.9 mΩ (Typical) | | **Operating Temperature** | -40°C to +125°C | | **Package Size** | 5.2mm x 5.2mm x 2.0mm | --- ### 2. Physical Construction The "SD" series uses a specific architecture to optimize performance in small footprints: * **Shielded Construction:** The inductor is magnetically shielded to minimize Electromagnetic Interference (EMI) with neighboring components. * **Ferrite Core:** Utilizes a high-density ferrite core to achieve high saturation levels. * **Flat Top:** The smooth top surface is designed for automated pick-and-place assembly. --- ### 3. Part Number Breakdown Understanding the nomenclature helps in identifying variants: | Segment | Meaning | | :--- | :--- | | **SD** | Series name (Low-profile, shielded inductor) | | **20** | Size code (approx. 2.0mm height) | | **-** | Separator | | **R47** | Inductance value (R = Decimal point; 0.47 microhenries) | --- ### 4. Common Applications Due to its low profile and high current capacity, the SD20-R47 is commonly used in: * **DC-DC Converters:** Buck, boost, and forward converters. * **Mobile Electronics:** Smartphones, tablets, and handheld devices. * **Power Supplies:** VRM (Voltage Regulator Modules) for CPUs and GPUs. * **Computer Peripherals:** SSDs and high-speed networking cards. --- ### 5. Identification and Handling When identifying these parts on a PCB, look for the marking "R47" on the top of the dark grey ferrite body. Because it is an SMD component, it is sensitive to moisture (MSL 1) and should be soldered according to J-STD-020 profiles to avoid internal cracking of the ferrite core.