The **DRQ73-2R2-R** is a high-performance, dual-winding inductor (coupled inductor) manufactured by **Eaton (formerly Bussmann/Coiltronics)**. It is part of the DRQ series, known for its high power density and versatile configurations. --- ### 1. Key Technical Specifications Below are the primary electrical and physical characteristics of the component: | Parameter | Specification | | :--- | :--- | | **Inductance** | 2.2 µH | | **Tolerance** | ±20% | | **Current Rating (Irms)** | 5.56 Amps | | **Saturation Current (Isat)** | 7.84 Amps | | **DC Resistance (DCR)** | 14.5 mΩ (Typ) | | **Operating Temperature** | -40°C to +125°C | | **Size / Dimension** | 7.6mm x 7.6mm x 3.55mm | | **Mounting Type** | Surface Mount (SMD/SMT) | --- ### 2. Physical Construction and Features The DRQ73-2R2-R is more than a simple coil; it is a **coupled inductor** consisting of two separate windings on a single ferrite core. * **Magnetically Shielded:** The drum core is enclosed in a ferrite sleeve, which minimizes Electromagnetic Interference (EMI) and protects nearby sensitive components. * **Dual Windings:** Because it has two identical windings, it can be connected in several ways: * **Series:** To double the inductance. * **Parallel:** To double the current capacity. * **1:1 Transformer:** To provide isolation or create a SEPIC/Zeta converter. * **High Efficiency:** Uses flat-wire or optimized winding techniques to keep DCR low, reducing heat loss. --- ### 3. Common Applications Due to its dual-coil nature, this part is frequently used in power management circuits: 1. **SEPIC Converters:** Used in battery-powered devices where the input voltage can be higher or lower than the output voltage. 2. **Flyback Transformers:** Acting as a small 1:1 transformer for isolated power supplies. 3. **DC-DC Converters:** Standard buck (step-down) or boost (step-up) circuits requiring high current in a small footprint. 4. **Common Mode Choke:** Can be used to filter out noise on power lines. --- ### 4. Circuit Implementation Examples Depending on how you solder the pins, the behavior changes: ```cpp // Connection Logic: // 1. Parallel: Connect Start-to-Start and End-to-End. // Result: 2.2uH, Higher Current Handling. // 2. Series: Connect End of Coil 1 to Start of Coil 2. // Result: 8.8uH (Inductance = L1 + L2 + 2M), Lower Current. ```