The **0805HT-R12T_L** is a specific part number for a surface-mount (SMD) high-temperature wire-wound chip inductor, typically manufactured by **Coilcraft**. --- ### 1. Part Number Breakdown Understanding the nomenclature helps identify the component's physical and electrical characteristics: | Code Segment | Meaning | Description | | :--- | :--- | :--- | | **0805** | Case Size | Dimensions are approx. 0.08 x 0.05 inches (2.0 x 1.25 mm). | | **HT** | Series | "High Temperature" series, designed for extreme environments. | | **R12** | Inductance Value | `R` acts as a decimal point. `0.12 µH` (or 120 nH). | | **T** | Tolerance | Typically represents $\pm 5\%$ or $\pm 10\%$ (varies by manufacturer spec). | | **L** | Termination/Packaging | Often indicates RoHS compliance/Lead-free or specific tape-and-reel options. | --- ### 2. Key Specifications The 0805HT series is distinct because it uses a ceramic core and wire-wound construction, allowing for high "Q" factors and high-frequency performance. | Parameter | Typical Value | | :--- | :--- | | **Inductance** | 120 nH (0.12 µH) | | **Construction** | Wire-wound on a ceramic core | | **Operating Temperature** | -40°C to +155°C (High Temp rating) | | **Self-Resonant Frequency (SRF)** | High (typically > 1 GHz) | | **DCR (DC Resistance)** | Low, allowing for efficient power handling | --- ### 3. Applications and Features * **High-Temperature Stability:** Unlike standard inductors that may fail or drift at 125°C, the "HT" series is rated for 155°C, making it ideal for automotive "under-the-hood" electronics and industrial sensors. * **RF Performance:** Because it is wire-wound on a ceramic core, it maintains high precision and high Q-factors at high frequencies, suitable for RF tuning and impedance matching. * **Compact Footprint:** The 0805 size is small enough for modern PCB density while being large enough for easy automated assembly. --- ### 4. Schematic Representation In a circuit diagram, this part is represented by the standard inductor symbol: ```text L1 (120nH) ----(UUUUU)---- 0805HT ```