The **FP1105R1-R20-R** is a high-current, shielded drum core inductor specifically designed for high-frequency power applications. It is manufactured by Eaton (formerly Cooper Bussmann/Coiltronics). --- ### 1. Key Technical Specifications | Parameter | Specification | Details | | :--- | :--- | :--- | | **Inductance** | 200 nH (0.20 µH) | Measured at 100 kHz, 0.1 Vrms | | **Current Rating ($I_{rms}$)** | 43 Amps | Temperature rise current | | **Saturation Current ($I_{sat}$)** | 85 Amps | Peak current before inductance drops 20% | | **DC Resistance (DCR)** | 0.42 mΩ (max) | Extremely low resistance to minimize heat | | **Operating Temperature** | -40°C to +125°C | Includes self-heating | | **Package / Case** | 11.0mm x 8.0mm x 4.9mm | Surface Mount Device (SMD) | --- ### 2. Part Number Breakdown The nomenclature provides specific details about the component's construction: * **FP1105**: The Series designation (Flat-Pac™ high current, high frequency). * **R1**: Version or revision control indicator. * **R20**: The inductance value. The "R" acts as a decimal point (R20 = 0.20 µH). * **-R**: RoHS compliant (lead-free). --- ### 3. Core Features and Benefits * **High Frequency Performance:** Optimized for switching frequencies up to 2 MHz. * **Ferrite Core Material:** Provides low core losses, making it highly efficient in high-speed DC-DC converters. * **Low DCR:** The use of flat wire or a solid copper plate design minimizes resistive losses, allowing the part to handle massive currents without overheating. * **Magnetic Shielding:** Reduces Electromagnetic Interference (EMI) by containing the magnetic flux within the inductor body. --- ### 4. Common Applications This inductor is typically found in high-performance power stages where space is limited but current requirements are high: 1. **Voltage Regulator Modules (VRMs):** Used in servers and workstations to power CPUs/GPUs. 2. **Multi-phase Buck Converters:** Ideal for distributing current across multiple phases. 3. **Point-of-Load (POL) Converters:** Used in networking and telecommunications equipment. 4. **Desktop and Server Motherboards:** Specifically for high-current power rails.