The **DRA73-221-R** is a high-performance, shielded power inductor designed primarily for automotive and industrial applications. It belongs to the **DRA Series** manufactured by **Eaton (formerly Bussmann/Coiltronics)**. --- ## 1. Key Technical Specifications The part number follows a specific nomenclature that defines its physical and electrical characteristics. | Parameter | Specification | | :--- | :--- | | **Inductance** | 220 µH | | **Tolerance** | ±20% | | **Current Rating (Irms)** | 0.692 Amperes (A) | | **Saturation Current (Isat)** | 0.811 Amperes (A) | | **DC Resistance (DCR)** | 0.942 Ohms (Ω) Typical | | **Operating Temperature** | -40°C to +165°C | | **Dimensions** | 7.6mm x 7.6mm x 3.55mm | --- ## 2. Core Features The "DRA" series is engineered for harsh environments where reliability is critical. * **Magnetically Shielded:** The component is enclosed in a ferrite core to minimize Electromagnetic Interference (EMI), which is essential for sensitive automotive electronics. * **High Temperature Rating:** With a maximum operating temperature of +165°C, it is suitable for "under-the-hood" automotive environments. * **AEC-Q200 Qualified:** It meets the stress test qualification for passive components used in the automotive industry. * **Mechanical Durability:** Designed to withstand high vibration and mechanical shock. --- ## 3. Applications Due to its high inductance and shielding, the DRA73-221-R is commonly used in: 1. **Automotive Electronics:** Power steering (EPS), airbag control units, and engine management systems. 2. **DC-DC Converters:** Used as a storage inductor in buck, boost, or buck-boost topologies. 3. **Industrial Controls:** Power supplies for sensors and automation equipment. 4. **LED Lighting:** Constant current drivers for automotive headlights or industrial signage. --- ## 4. Part Number Breakdown Understanding the code `DRA73-221-R`: * **DRA:** Product Series (High Power density, Shielded). * **73:** Size code (approx. 7mm width, 3mm height). * **221:** Inductance value in Microhenries. (The first two digits are significant; the third is the multiplier: $22 \times 10^1 = 220$ µH). * **R:** RoHS compliant.