The **HCM1707-4R7-R** is a high-current, automotive-grade power inductor manufactured by Eaton (formerly Cooper Bussmann). It belongs to the HCM series, which is designed to handle high transient current spikes and provide high efficiency in power conversion circuits. --- ### ## Technical Specifications The following table summarizes the primary electrical and physical characteristics: | Parameter | Specification | | :--- | :--- | | **Inductance** | 4.7 µH | | **Tolerance** | ±20% | | **DC Resistance (DCR)** | 9.0 mΩ (Typical) / 10.35 mΩ (Max) | | **Rated Current (Irms)** | 16.5 A | | **Saturation Current (Isat)** | 18 A | | **Operating Temperature** | -55°C to +125°C | | **Package / Case** | 1707 (Approx. 17.5mm x 17.2mm) | | **Construction** | Iron Powder Core (Shielded) | --- ### ## Key Features * **High Current Capability:** Designed to carry high currents with minimal self-heating. * **Magnetically Shielded:** The molded iron powder construction minimizes Electro-Magnetic Interference (EMI). * **Low Core Loss:** Optimized for high-frequency DC-DC converters. * **AEC-Q200 Qualified:** This specific series is often rated for automotive use, meaning it can withstand harsh vibrations and thermal cycling. --- ### ## Internal Structure & Working The component consists of a copper wire coil wound inside a composite of iron powder and resin. This "molded" construction allows for: 1. **Soft Saturation:** Unlike ferrite cores that drop inductance sharply when current increases, this part loses inductance gradually, preventing sudden circuit failure. 2. **Environmental Protection:** The molding protects the copper wire from oxidation and mechanical stress. --- ### ## Common Applications The HCM1707-4R7-R is typically found in the following circuits: * **Voltage Regulator Modules (VRM):** Used in high-end servers and desktop CPUs. * **Automotive Electronics:** Power steering, lighting, and infotainment systems. * **DC-DC Converters:** Point-of-load (POL) converters where high efficiency is required. * **Battery Powered Systems:** To manage high-current discharge paths.