The **SDQ25-471-R** is a specific electronic component belonging to the **SDQ series** manufactured by Eaton (formerly Cooper Bussmann/Coiltronics). It is a high-power density, dual-winding toroidal inductor/transformer. --- ### 1. Technical Specifications The part number follows a specific nomenclature that defines its electrical characteristics: | Parameter | Specification | | :--- | :--- | | **Inductance** | 470 µH (indicated by the code '471') | | **Tolerance** | ±20% | | **DC Resistance (DCR)** | ~2.32 Ω (per winding) | | **Isat (Saturation Current)** | ~0.34 A | | **Irms (Heating Current)** | ~0.41 A | | **Configuration** | Dual Winding (Can be series or parallel) | | **Mounting Type** | Surface Mount (SMD) | --- ### 2. Key Features * **Dual Winding Versatility:** The device contains two separate windings that can be connected in different ways: * **Series:** For higher inductance (4x the base value). * **Parallel:** For higher current capacity (2x the base value). * **Transformer:** Used as a 1:1 ratio transformer or SEPIC inductor. * **Magnetic Shielding:** The toroidal construction inherently provides low EMI (Electromagnetic Interference) radiation. * **Small Footprint:** Designed for high power density in space-constrained PCB layouts. * **RoHS Compliant:** The "-R" suffix indicates full compliance with environmental standards. --- ### 3. Applications The SDQ25 series is commonly found in power management circuits, specifically: * **SEPIC Converters:** Used as a coupled inductor in Single-Ended Primary-Inductor Converters. * **Voltage Isolation:** Can act as a 1:1 transformer for providing isolated power rails. * **Filtering:** High-frequency noise suppression in DC-DC converters. * **Inductive Storage:** Energy storage for buck/boost regulators. --- ### 4. Part Number Breakdown `SDQ25 - 471 - R` * **SDQ25:** Series name and physical size (Approx. 5.2mm x 5.2mm x 2.5mm). * **471:** Inductance code ($47 \times 10^1 = 470$ microhenries). * **R:** RoHS compliant version.