The **TP4212-8R2M-R** is a high-performance, surface-mount (SMD) power inductor. It is commonly used in power management circuits, specifically for DC-DC converters, to store energy in a magnetic field. ### 1. Key Technical Specifications | Parameter | Value | | :--- | :--- | | **Inductance** | 8.2 µH | | **Tolerance** | ±20% (indicated by 'M') | | **DCR (Direct Current Resistance)** | ~40 mΩ (Typical) | | **Saturation Current ($I_{sat}$)** | ~2.5A - 3.5A (Depends on manufacturer) | | **Operating Temperature** | -40°C to +125°C | | **Package / Case** | 4.2mm x 4.2mm x 1.2mm (approx.) | --- ### 2. Part Number Breakdown The nomenclature follows a standard industry format for magnetic components: * **TP**: Series code (usually identifying the manufacturer's specific low-profile high-current line). * **4212**: Physical dimensions. "42" indicates a footprint of approx 4.2mm x 4.2mm; "12" indicates a height of 1.2mm. * **8R2**: The inductance value. The 'R' acts as a decimal point. $8.2$ microhenries ($\mu H$). * **M**: Tolerance code ($M = \pm20\%$). * **R**: Often denotes "RoHS Compliant" or "Tape and Reel" packaging. --- ### 3. Electronic Characteristics * **Magnetic Shielding:** These inductors are typically shielded. This prevents electromagnetic interference (EMI) from leaking out and affecting nearby sensitive components on the PCB. * **Low Profile:** With a height of only 1.2mm, it is designed for ultra-thin electronics like smartphones, tablets, and wearable devices. * **Energy Storage:** In a switching regulator, this part stores energy when the MOSFET is ON and releases it to the load when the MOSFET is OFF, smoothing out the current. ### 4. Common Applications 1. **Buck/Boost Converters:** Used in voltage regulators to step down or step up battery voltage. 2. **LED Drivers:** Providing constant current for backlighting or flash modules. 3. **Portable Devices:** Ideal for HDD/SSD power rails, cameras, and mobile communication modules due to the small footprint. --- ### 5. Recommended PCB Footprint When designing a PCB for this part, ensure the landing pads allow for thermal dissipation. ```markdown (Inductor Pad Layout) [ PAD ] <--- 1.5mm ---> [ PAD ] | | 4.2mm 4.2mm ```