### Overview of the SD18-1R5-R The **SD18-1R5-R** is a high-power density, low-profile power inductor manufactured by **Eaton (formerly Coiltronics)**. It belongs to the SD series, which is designed for applications requiring compact footprints and high efficiency. --- ### Technical Specifications | Parameter | Specification | | :--- | :--- | | **Inductance** | 1.5 µH | | **Tolerance** | ±20% | | **DC Resistance (DCR)** | 27.6 mΩ (Nominal) | | **Rated Current (Irms)** | 2.58 Amps | | **Saturation Current (Isat)** | 3.52 Amps | | **Shielding** | Shielded (Magnetic) | | **Operating Temperature** | -40°C to +125°C | | **Package / Case** | 5.20mm x 5.20mm x 1.80mm | --- ### Key Features and Construction 1. **Magnetic Shielding**: The part is ferrite-shielded, which minimizes Electromagnetic Interference (EMI). This is crucial for dense PCB layouts where components are placed close to sensitive analog circuits. 2. **Low Profile**: With a maximum height of only **1.8mm**, it is ideal for slim electronics like tablets, smartphones, and wearable devices. 3. **Ferrite Core**: Uses a high-frequency ferrite core material that ensures low core losses, contributing to higher energy efficiency in power conversion. 4. **Tape and Reel Packaging**: The "-R" suffix indicates that the part is RoHS compliant and typically supplied in tape and reel for automated SMT (Surface Mount Technology) assembly. --- ### Common Applications The SD18-1R5-R is primarily used in DC-DC converter circuits. Typical use cases include: * **Buck Converters**: Stepping down voltage for microprocessors. * **Boost Converters**: Increasing battery voltage for LED backlighting. * **Handheld Devices**: Mobile phones, GPS units, and digital cameras. * **Computer Peripherals**: SSDs and network interface cards. --- ### Typical Circuit Implementation In a standard Buck Converter, the SD18-1R5-R would be placed as the energy storage element between the switching node and the output capacitor. ```mermaid graph LR A[Switching Node] --> B((SD18-1R5-R)) B --> C[Vout / Load] B --- D[Output Capacitor] D --- GND ```