## Technical Overview: HC8-3R5-R High Current Inductor The **HC8-3R5-R** is a high-current, low-profile power inductor manufactured by **Eaton (formerly Cooper Bussmann/Coiltronics)**. It belongs to the **HC8 Series**, which is specifically designed for high-density, high-current power applications. --- ### 1. Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Inductance** | 3.5 µH (Microhenries) | | **Tolerance** | ±20% | | **Rated Current (Irms)** | ~18.5 A (typical) | | **Saturation Current (Isat)** | ~25.0 A (typical) | | **DC Resistance (DCR)** | ~3.3 mΩ (Max) | | **Operating Temperature** | -40°C to +125°C | | **Mounting Type** | Surface Mount (SMD) | | **Dimensions** | 10.9mm x 10.4mm x 4.0mm | --- ### 2. Physical Construction and Features * **Core Material:** Powdered Iron core technology. This provides excellent energy storage density and soft saturation characteristics (the inductance drops gradually rather than abruptly as current increases). * **Shielding:** It is a **shielded** design, which minimizes Electromagnetic Interference (EMI) to surrounding components. * **Rugged Design:** The HC8 series is known for its high-temperature stability and mechanical robustness, making it suitable for demanding environments. * **RoHS Compliant:** The "-R" suffix at the end of the part number denotes that the component is Lead-Free and RoHS compliant. --- ### 3. Common Applications The HC8-3R5-R is typically found in high-efficiency power supply circuits, including: 1. **Multi-phase Regulators:** Used in high-end CPU and GPU power delivery. 2. **Voltage Regulator Modules (VRMs):** Found on server and desktop motherboards. 3. **DC-DC Converters:** Point-of-Load (POL) modules for industrial and telecommunications equipment. 4. **Battery Powered Systems:** Where low DCR is critical to maximizing battery life and reducing heat waste. --- ### 4. Circuit Symbol and Footprint ```markdown (Inductor Symbol) L1 ---( )--- 3.5uH ``` * **Polarity:** Inductors are non-polarized components; they can be installed in either direction on the PCB. * **Footprint Note:** Ensure the PCB pads are large enough to handle the high current (up to 25A) to prevent trace overheating. ---