The **SCI0805S-R18F** is a surface-mount (SMD) wire-wound chip inductor. It is commonly used in high-frequency applications where high precision and high "Q" factors are required. ### 1. Part Number Breakdown Understanding the nomenclature helps identify the component's exact specifications: | Segment | Meaning | Detail | | :--- | :--- | :--- | | **SCI** | Series Name | Standard Chip Inductor | | **0805** | Case Size | 2.0mm x 1.25mm (Imperial 0805) | | **S** | Material/Type | Standard / Wire-wound | | **R18** | Inductance Value | 0.18 µH (180 nH) | | **F** | Tolerance | ±1% | --- ### 2. Technical Specifications The typical electrical characteristics for this specific 180nH inductor are outlined below: | Parameter | Typical Value | | :--- | :--- | | **Inductance** | 180 nH (0.18 µH) | | **Tolerance** | ±1% | | **Quality Factor (Q min)** | 45 @ 100MHz | | **Self-Resonant Frequency (SRF)** | 1100 MHz (Minimum) | | **DC Resistance (DCR max)** | 0.70 Ω | | **Rated Current (I DC)** | 400 mA | | **Operating Temperature** | -40°C to +125°C | --- ### 3. Key Features & Construction * **Wire-Wound Technology:** Unlike multilayer inductors, these use a ceramic core with copper wire wrapped around it. This results in much higher **Q factors** and better current handling. * **Tight Tolerance:** The "F" suffix denotes a 1% tolerance, which is critical for RF tuning circuits and filters where frequency drift must be minimized. * **High SRF:** The high self-resonant frequency ensures the component behaves like an inductor even at gigahertz ranges. --- ### 4. Common Applications Due to its high precision and high-frequency performance, the SCI0805S-R18F is typically found in: 1. **RF Tranceivers:** Used in matching networks for antennas. 2. **Filter Circuits:** Low-pass, high-pass, and band-pass filters for wireless communication. 3. **VCOs:** Voltage Controlled Oscillators requiring stable inductance. 4. **Signal Conditioning:** High-speed data lines to suppress noise without degrading the signal. ---