The **DR1040-5R2-R** is a high-performance, surface-mount (SMD) power inductor commonly used in DC-DC converters and voltage regulation modules. It is part of the DR series manufactured by **Eaton (formerly Coiltronics)**. --- ### 1. Technical Specifications The following table highlights the primary electrical and physical characteristics of the component: | Parameter | Specification | | :--- | :--- | | **Inductance** | 5.2 µH | | **Tolerance** | ±20% | | **Current Rating (Isat)** | 5.50 A (Saturation Current) | | **Current Rating (Irms)** | 4.48 A (RMS Current) | | **DC Resistance (DCR)** | 19.3 mΩ (Typical) | | **Shielding** | Shielded (Magnetically) | | **Operating Temperature** | -40°C to +125°C | | **Dimensions** | 10.3mm x 10.5mm x 4.0mm | --- ### 2. Breakdown of the Part Number Understanding the nomenclature helps in identifying variants within the same family: * **DR**: Series name (Drum Core). * **1040**: Physical size (approx. 10mm wide/long and 4.0mm high). * **5R2**: Inductance value. The "R" acts as a decimal point, signifying **5.2 µH**. * **-R**: RoHS compliant / Lead-free. --- ### 3. Key Electronic Features * **Magnetic Shielding:** The component is shielded, which minimizes Electromagnetic Interference (EMI). This is crucial for densely packed circuit boards where noise can interfere with sensitive components. * **High Power Density:** Designed to handle high current in a relatively small footprint. * **Drum Core Construction:** Provides a robust structure and efficient energy storage for switching power supplies. * **Low Core Loss:** Optimized for high-frequency applications (up to 1 MHz), reducing heat generation and increasing overall power efficiency. --- ### 4. Common Applications This inductor is typically found in the following circuits: 1. **Buck/Boost Converters:** Used as the energy storage element in step-down or step-up voltage regulators. 2. **Laptops and Graphics Cards:** Found in VRM (Voltage Regulator Module) circuits for CPUs and GPUs. 3. **Industrial Controls:** Used in power supplies for PLC and automation equipment. 4. **LED Drivers:** Provides steady current to high-brightness LED arrays. ---