### Technical Overview of SRN2012-R47M The **SRN2012-R47M** is a semi-shielded power inductor manufactured by Bourns. It is designed primarily for DC/DC converter applications where space is limited and high efficiency is required. --- ### 1. Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Inductance** | 0.47 µH | | **Tolerance** | ±20% | | **Case Size (Metric)** | 2012 (2.0 mm x 1.2 mm) | | **Height (Max)** | 1.2 mm | | **Rated Current (Irms)** | 2.5 Amperes | | **Saturation Current (Isat)** | 3.5 Amperes | | **DC Resistance (DCR Max)** | 36 mΩ | | **Operating Temperature** | -40 °C to +125 °C | --- ### 2. Breakdown of the Part Number The nomenclature used by Bourns provides specific details about the component's physical and electrical properties: * **SRN**: Series name (Semi-shielded Power Inductor). * **2012**: Physical dimensions in millimeters (2.0mm length x 1.2mm width). * **R47**: The inductance value. "R" acts as a decimal point, so R47 = **0.47 µH**. * **M**: The tolerance code. "M" represents **±20%**. --- ### 3. Structural Composition This component utilizes a **semi-shielded** construction, which offers a middle ground between unshielded and fully shielded inductors: * **Core Material:** Typically a ferrite core. * **Shielding:** Uses a magnetic epoxy resin coating. This reduces magnetic field radiation (EMI) compared to non-shielded types but is more cost-effective and compact than a full metal-can shield. * **Terminations:** Tin-plated copper (lead-free/RoHS compliant). --- ### 4. Common Applications Due to its high saturation current and small footprint, it is commonly found in: 1. **Smartphones and Tablets:** Low-profile power management modules. 2. **DC/DC Converters:** High-frequency switching regulators. 3. **Wearable Electronics:** Devices requiring high power density in a tiny form factor. 4. **SSD Storage:** Filtering and power regulation for high-speed data drives. --- ### 5. Performance Considerations * **Self-Resonant Frequency (SRF):** At 0.47 µH, this inductor has a high SRF, making it suitable for high-frequency switching power supplies (often above 1 MHz). * **Saturation (Isat):** The 3.5A saturation current is the point where the inductance drops by 30%. Designers must ensure peak circuit currents do not exceed this to avoid loss of regulation.