## Technical Overview: DR1050-821-R Inductor The **DR1050-821-R** is a high-power, shielded drum core inductor manufactured by **Eaton (formerly Coiltronics)**. It is part of the DR series, specifically designed for applications requiring high efficiency and low electromagnetic interference (EMI). --- ### 1. Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Inductance** | 820 µH | | **Tolerance** | ±20% | | **DC Resistance (DCR)** | 1.35 Ω (Nominal) | | **Rated Current (Irms)** | 0.52 Amps (Continuous) | | **Saturation Current (Isat)** | 0.61 Amps (Peak) | | **Shielding** | Magnetically Shielded | | **Operating Temperature** | -40°C to +125°C | --- ### 2. Physical Characteristics The "1050" in the part number refers to its physical dimensions, which are critical for PCB layout design: * **Footprint:** Approximately 10.5 mm x 10.3 mm. * **Height:** 5.0 mm maximum. * **Mounting:** Surface Mount Device (SMD). * **Core Material:** Ferrite core, which offers low core losses at high frequencies. --- ### 3. Functional Breakdown #### Magnetically Shielded Design The DR1050 series features a closed magnetic path. This is vital for high-density boards because it minimizes "stray" magnetic fields that could interfere with neighboring sensitive components. #### Saturation Current (Isat) vs. RMS Current (Irms) * **Isat (0.61A):** The point where the inductance drops by a specified percentage (usually 30%). If your circuit exceeds this, the inductor loses its effectiveness. * **Irms (0.52A):** The continuous current that causes a 40°C temperature rise above ambient. This is the thermal limit for safe operation. --- ### 4. Common Applications The DR1050-821-R is typically used in power management circuits, including: 1. **DC-DC Converters:** Used in buck, boost, and forward converters. 2. **Output Filters:** Smoothing ripples in power supplies. 3. **LED Drivers:** Providing constant current for lighting applications. 4. **Battery Powered Equipment:** Where high efficiency is needed to extend battery life. --- ### 5. Part Number Decoding `DR 1050 - 821 - R` * **DR:** Series Name (Drum Core). * **1050:** Size dimensions (10mm wide, 5.0mm high). * **821:** Inductance Value (82 followed by 1 zero = 820 µH). * **-R:** RoHS compliant (Lead-free).