The **1812SMS-R10JLC** is a high-performance, surface-mount (SMD) wirewound inductor, typically manufactured by **Coilcraft**. It belongs to the 1812SMS series, which is designed for high-frequency applications where high Q-factors and tight tolerances are critical. --- ### 1. Part Number Breakdown Understanding the alphanumeric code helps identify the specific characteristics of the component: | Segment | Meaning | Details | | :--- | :--- | :--- | | **1812** | Case Size | 0.18 x 0.12 inches (approx. 4.5 x 3.2 mm) | | **SMS** | Series Type | Surface Mount, Spring/Air Core Inductor | | **R10** | Inductance Value | R10 = 0.10 µH (100 nH) | | **J** | Tolerance | ±5% | | **L** | Termination | Silver-palladium-platinum-glass frit | | **C** | Packaging | 7″ machine-ready reel (Carrier tape) | --- ### 2. Technical Specifications Below are the typical electrical parameters for this specific part: | Parameter | Value | | :--- | :--- | | **Inductance** | 100 nH (0.10 µH) | | **Tolerance** | ±5% | | **Quality Factor (Q min)** | 100 at 150 MHz | | **Self-Resonant Frequency (SRF)** | 1.1 GHz (Typical) | | **DC Resistance (DCR max)** | 0.44 Ohms | | **Current Rating (Irms)** | 1.1 Amps | | **Operating Temperature** | -40°C to +125°C | --- ### 3. Key Features and Construction * **Air Core Technology:** Unlike ferrite-core inductors, this uses an "air core" (no magnetic material inside). This ensures zero core losses and prevents magnetic saturation, making it ideal for high-current and high-frequency stability. * **High Q-Factor:** The "Spring" construction provides exceptionally high Q-factors, which results in very low signal loss in resonant circuits. * **Physical Robustness:** The wire is wound around a ceramic header or encapsulated in a way that provides flat tops for easy pick-and-place assembly. --- ### 4. Common Applications Due to its high frequency and high Q characteristics, the 1812SMS-R10JLC is commonly used in: 1. **RF Circuits:** Used in oscillators and impedance matching networks. 2. **Filters:** High-order bandpass, lowpass, and highpass filters. 3. **Telecommunications:** Base stations, cellular infrastructure, and satellite equipment. 4. **Medical Equipment:** MRI and high-frequency imaging systems where magnetic interference must be minimized. ---