The **LD2-471-R** is a specific model of a surface-mount (SMD) power inductor part of the **LD2 series** manufactured by **Coiltronics** (now a brand under **Eaton**). These components are primarily used for energy storage and filtering in power management circuits. --- ## 1. Technical Specifications Below are the primary electrical and physical characteristics of the LD2-471-R: | Parameter | Specification | Details | | :--- | :--- | :--- | | **Inductance** | 470 µH | Nominal inductance value | | **Tolerance** | ±20% | Standard deviation allowance | | **DC Resistance (DCR)** | ~1.34 Ω | Typical resistance of the copper winding | | **Rated Current ($I_{rms}$)** | 0.38 A | Current causing a 40°C temperature rise | | **Saturation Current ($I_{sat}$)** | 0.44 A | Current where inductance drops by 10% | | **Package Size** | LD2 (10mm x 9mm) | Surface mount footprint | | **Termination** | RoHS Compliant | Matte Tin over Copper | --- ## 2. Part Number Breakdown Understanding the nomenclature helps in identifying variants: * **LD2**: Refers to the physical size/series (Size 2). * **471**: The Inductance code. * The first two digits (47) are the value. * The third digit (1) is the multiplier (number of zeros). * $47 \times 10^1 = 470$ µH. * **-R**: Indicates the part is **RoHS Compliant** (lead-free). --- ## 3. Physical Construction The LD2 series features a **drum core** construction: 1. **Core Material:** Ferrite core which provides high permeability and low core losses. 2. **Winding:** Enameled copper wire wound around the ferrite spool. 3. **Shielding:** This specific series is typically **unshielded**. This means it is cost-effective but may have higher electromagnetic interference (EMI) compared to shielded versions. 4. **Terminals:** Robust solder pads designed for reflow soldering. --- ## 4. Common Applications Due to its 470 µH inductance and moderate current handling, it is found in: * **DC-DC Converters:** Used in Buck or Boost converters for voltage regulation. * **Filtering:** Acting as a low-pass filter to remove high-frequency noise from power lines. * **Energy Storage:** Storing energy in the magnetic field during the "on" cycle of a switching regulator. * **Consumer Electronics:** Power supplies for LED drivers, LCD displays, and portable devices. ---