## Electronic Component Overview: SD3812-151-R The **SD3812-151-R** is a high-power density, low-profile shielded drum core inductor manufactured by **Eaton (formerly Cooper Bussmann)**. It is part of the SD3812 series, designed for applications where space is limited and EMI (Electromagnetic Interference) shielding is required. ### 1. Key Specifications | Parameter | Value | | :--- | :--- | | **Inductance** | 150 µH | | **Tolerance** | ±20% | | **DC Resistance (DCR)** | 1.83 Ω (Typical) | | **Saturation Current ($I_{sat}$)** | 0.26 A | | **RMS Current ($I_{rms}$)** | 0.38 A | | **Shielding** | Magnetically Shielded | | **Operating Temperature** | -40°C to +125°C | --- ### 2. Physical Characteristics * **Form Factor:** Surface Mount Device (SMD). * **Dimensions:** Approximately 4.0mm x 4.0mm with a very low height of **1.2mm**. * **Construction:** Ferrite drum core with a ferrite sleeve to contain magnetic flux, reducing interference with surrounding components. * **Compliance:** RoHS compliant and lead-free (indicated by the **-R** suffix). --- ### 3. Functional Applications This component is typically used in power management circuits where voltage regulation and noise filtering are critical. Common applications include: 1. **DC-DC Converters:** Used in "Buck" (step-down) or "Boost" (step-up) converters to store energy. 2. **Mobile Electronics:** Ideal for smartphones, tablets, and wearables due to the 1.2mm ultra-low profile. 3. **LED Drivers:** Provides stable current regulation for backlighting or flash units. 4. **Noise Filtering:** Acts as a low-pass filter to decouple power supply lines from sensitive digital ICs. --- ### 4. Part Number Breakdown Understanding the nomenclature helps in identifying variants: | Segment | Meaning | | :--- | :--- | | **SD** | Series name (Shielded Drum) | | **3812** | Size code (approx. 3.8mm footprint, 1.2mm height) | | **151** | Inductance value: 15 followed by 1 zero = **150 µH** | | **-R** | RoHS compliant |