The **FP1109B1-R300-R** is a high-performance, high-current power inductor manufactured by **Eaton (formerly Cooper Bussmann)**. It belongs to the FP1109 series, which is specifically designed for high-frequency voltage regulator modules (VRMs). --- ### 1. Key Technical Specifications The part number encodes specific characteristics of the component: | Feature | Specification | | :--- | :--- | | **Inductance** | 300 nH (0.30 µH) | | **Tolerance** | ±10% | | **Saturation Current ($I_{sat}$)** | ~37 Amperes (at 25°C) | | **RMS Current ($I_{rms}$)** | ~28 Amperes | | **DC Resistance (DCR)** | 0.42 mΩ (Typical) | | **Operating Temperature** | -40°C to +125°C | | **Dimensions (L x W x H)** | 11.0 x 8.0 x 9.0 mm | --- ### 2. Physical Construction The "B1" in the part number refers to the specific mechanical package style. * **Core Material:** Ferrite core technology, which provides very low core losses at high frequencies. * **Design:** It is a SMT (Surface Mount Technology) component with a "flat-pac" construction. This allows for a very low profile while maintaining high power density. * **Lead-Free:** The "-R" suffix indicates that the part is RoHS compliant. --- ### 3. Applications and Usage This specific inductor is engineered for high-current, low-voltage power conversion. Common use cases include: * **Multi-phase VRMs:** Used in CPU/GPU power delivery for servers and workstations. * **DC-DC Converters:** Point-of-Load (POL) modules. * **Data Storage:** Powering high-speed SSD controllers or RAID arrays. ### 4. Advantages * **Extremely Low DCR:** At 0.42 mΩ, it minimizes power dissipation (heat) during operation, increasing overall system efficiency. * **High Saturation:** The ferrite core ensures that the inductance remains stable even under high current spikes. * **Vertical Space Saving:** The 1109 footprint is optimized for tight PCB layouts near processors. --- ### 5. Part Number Breakdown ```text FP 1109 B 1 - R300 - R | | | | | | | | | | | +-- RoHS Compliant | | | | +------- Inductance Value (R300 = 0.300 µH) | | | +------------ Revision/Variation | | +-------------- Mechanical Version (B) | +------------------ Dimensions (11.0mm x 9.0mm approx) +---------------------- Series Name (Flat-Pac) ```