The **DR125-101-R** is a high-power, shielded surface-mount (SMT) inductor manufactured by Eaton (formerly Cooper Bussmann). It belongs to the DR series, which is known for its high power density and efficiency in DC-DC converter applications. --- ## 1. Technical Specifications The part number "101" indicates the inductance value, and "R" signifies RoHS compliance. | Parameter | Specification | | :--- | :--- | | **Inductance** | 100 µH | | **Tolerance** | ±20% | | **Rated Current (Irms)** | 1.91 Amps (Typical) | | **Saturation Current (Isat)** | 2.18 Amps (Typical) | | **DC Resistance (DCR)** | 0.170 Ohms (Max) | | **Operating Temperature** | -40°C to +125°C | | **Shielding** | Magnetically Shielded | --- ## 2. Key Features ### A. Magnetic Shielding The inductor is ferrite-shielded. This minimizes **Electromagnetic Interference (EMI)**, making it ideal for densely packed circuit boards where noise could interfere with nearby sensitive components. ### B. High Power Density The DR125 series is designed to handle high current levels relative to its physical footprint (approx. 12.5mm x 12.5mm x 6.0mm). ### C. Construction * **Core Material:** Ferrite. * **Termination:** Lead-free, tin-plated copper. * **Mounting:** SMT (Surface Mount Technology) for automated pick-and-place assembly. --- ## 3. Common Applications The DR125-101-R is typically used in power management circuits, specifically: 1. **Buck/Boost Converters:** Acting as an energy storage element in DC-DC voltage regulation. 2. **Computer Peripherals:** Used in laptops, servers, and storage drives. 3. **Industrial Electronics:** Providing stable power for sensors and controllers. 4. **LED Lighting:** Used in driver circuits to maintain constant current. --- ## 4. Part Number Breakdown Understanding the nomenclature helps in identifying variants: * **DR:** Series Name (Drum Core). * **125:** Dimensions (approx. 12.5mm diameter/width). * **101:** Inductance Code (10 + one zero = 100µH). * **R:** RoHS Compliant.