The **HCF1305-4R7-R** is a high-current, automotive-grade power inductor manufactured by Eaton (formerly Cooper Bussmann/Coiltronics). It is part of the HCF1305 series, known for its high power density and reliability in harsh environments. --- ### 1. Key Technical Specifications The part number follows a specific nomenclature that defines its physical and electrical properties. | Parameter | Value / Specification | | :--- | :--- | | **Inductance** | 4.7 µH | | **Tolerance** | ±20% | | **DCR (Direct Current Resistance)** | 10.4 mΩ (Max) | | **Isat (Saturation Current)** | 11.0 A (Typical) | | **Irms (Heating Current)** | 10.5 A (Typical) | | **Operating Temperature** | -40°C to +125°C | | **Package Size** | 12.5mm x 12.9mm x 5.0mm (Surface Mount) | --- ### 2. Core Features * **High Current Handling:** Designed to manage high saturation currents without the core "bottoming out" quickly. * **Low Core Loss:** Utilizes a ferrite core material that minimizes energy loss, making it highly efficient for high-frequency switching. * **Automotive Grade:** It is **AEC-Q200 Grade 1** qualified, meaning it is tested for high vibration, thermal shock, and mechanical stress. * **Shielded Construction:** The design reduces Electromagnetic Interference (EMI), which is critical for sensitive surrounding circuits. --- ### 3. Application Use Cases This component is primarily used in power management stages where voltage conversion is necessary: 1. **DC-DC Converters:** Used as a storage element in Buck (step-down) or Boost (step-up) converters. 2. **Voltage Regulator Modules (VRM):** Provides stable power to microprocessors and GPUs. 3. **Automotive Electronics:** Powering Advanced Driver Assistance Systems (ADAS), infotainment, and LED lighting. 4. **Industrial Power Supplies:** Suitable for distributed power systems and battery-powered equipment. --- ### 4. Part Number Breakdown ```text HCF 1305 - 4R7 - R | | | | | | | +-- RoHS Compliant | | +------- Inductance Value (4R7 = 4.7 µH) | +-------------- Size Dimensions (approx. 13x5mm) +------------------- High Current Ferrite (Series Name) ```