The **DR1040-1R5-R** is a high-power, shielded surface-mount (SMD) inductor manufactured by Eaton (formerly Cooper Bussmann/Coiltronics). It is part of the DR series, known for high power density and efficiency in a compact footprint. --- ### 1. Key Technical Specifications | Parameter | Value / Description | | :--- | :--- | | **Inductance** | 1.5 µH | | **Tolerance** | ±30% | | **Current Rating (Irms)** | 6.51 Amps (Temperature rise current) | | **Saturation Current (Isat)** | 10.5 Amps (Current at which inductance drops) | | **DC Resistance (DCR)** | 9.0 mΩ (Max) | | **Operating Temperature** | -40°C to +125°C | | **Package / Case** | 10.3mm x 10.5mm x 4.0mm | --- ### 2. Functional Components & Materials * **Ferrite Core:** The part uses a drum core construction. Ferrite is used to provide high magnetic permeability while keeping eddy current losses low at high frequencies. * **Magnetic Shielding:** It is a "shielded" inductor. This means the magnetic field is contained within the component, significantly reducing Electromagnetic Interference (EMI) with neighboring components on the PCB. * **Windings:** Uses high-quality copper wire wound around the core. The low DCR (9.0 mΩ) ensures minimal power loss through heat. --- ### 3. Applications The DR1040-1R5-R is primarily designed for power management circuits where high efficiency is required: * **DC-DC Converters:** Buck, boost, and forward converters. * **Voltage Regulator Modules (VRMs):** Used in laptops and servers to regulate CPU power. * **Battery Powered Devices:** High efficiency extends battery life by reducing energy wasted as heat. * **Output Filter:** Smoothing out current ripples in switching power supplies. --- ### 4. Part Number Breakdown The nomenclature follows a specific logic: * **DR:** Product Series (Drum Core, Shielded). * **1040:** Dimensions (approx. 10mm diameter, 4.0mm height). * **1R5:** Inductance value (1.5 microhenries). * **-R:** RoHS compliant (Lead-free). ---