The **LD1-2R2-R** is a specific electronic component belonging to the **LD series of power inductors**, manufactured by **Eaton (formerly Cooper Bussmann)**. It is a surface-mount (SMD) device commonly used in power management circuits. ### 1. Component Breakdown The part number follows a specific nomenclature that describes its physical and electrical characteristics: | Part Segment | Meaning | Details | | :--- | :--- | :--- | | **LD1** | **Series/Size** | Refers to the physical dimensions (approx. 4.45mm x 4.06mm). | | **2R2** | **Inductance Value** | **2.2 µH** (R acts as the decimal point). | | **-R** | **RoHS Compliant** | Indicates the part is lead-free and meets environmental standards. | --- ### 2. Key Technical Specifications Based on the datasheet for the LD series, the 2.2µH variant typically features the following parameters: * **Inductance:** 2.2 µH ±20% * **Rated Current ($I_{rms}$):** The current that causes a 40°C temperature rise (typically ~2.4A to 2.8A for this size). * **Saturation Current ($I_{sat}$):** The current at which inductance drops by a specific percentage (typically ~2.5A). * **DC Resistance (DCR):** Usually in the range of 0.040Ω to 0.060Ω (Max). * **Operating Temperature:** -40°C to +125°C. --- ### 3. Construction and Features * **Ferrite Core:** High-density ferrite material ensures high efficiency and low core losses. * **Shielding:** These are **unshielded** or semi-shielded inductors, meaning they are cost-effective but may have some electromagnetic interference (EMI) leakage compared to fully shielded types. * **Low Profile:** Designed for space-constrained applications on Printed Circuit Boards (PCBs). --- ### 4. Typical Applications The LD1-2R2-R is primarily used in DC-DC conversion and filtering: 1. **Buck/Boost Converters:** Used in voltage regulators for laptops, mobile devices, and handheld electronics. 2. **Filtering:** Used in LC filters to smooth out ripple current in power supplies. 3. **LED Drivers:** Managing current flow in lighting circuits. 4. **Peripheral Power:** Providing stable power to disk drives or network cards. --- ### 5. Equivalent Considerations If you are looking for a replacement, you must match: * **Footprint:** The 4.4mm x 4.0mm land pattern. * **Current Rating:** Ensure the replacement can handle the same or higher $I_{rms}$ and $I_{sat}$. * **DCR:** A higher resistance will lead to more heat and lower efficiency.