The **CTMC1812-R18K** is a specific surface-mount technology (SMT) power inductor, commonly used in radio frequency (RF) and signal filtering circuits. Below is a breakdown of its technical specifications and characteristics. --- ### 1. Technical Specifications The alphanumeric code provides key information about the component's physical size and electrical properties. | Parameter | Specification | Description | | :--- | :--- | :--- | | **Part Series** | CTMC1812 | Molded Chip Inductor, 1812 Case Size | | **Inductance** | 0.18 µH | Represented by "R18" (R = decimal point) | | **Tolerance** | ±10% | Represented by "K" | | **Case Size (Inch)** | 1812 | Dimensions: 0.18" x 0.12" (approx. 4.5mm x 3.2mm) | | **Material** | Ferrite Core | Provides high magnetic permeability | | **Structure** | Wire-wound / Molded | High durability and protection against environment | --- ### 2. Electrical Performance While specific values can vary slightly by manufacturer (such as Central Technologies), the typical performance profile for a 0.18 µH 1812 inductor is as follows: * **Test Frequency:** Typically measured at 25.2 MHz. * **Self-Resonant Frequency (SRF):** Usually high (above 400 MHz), making it suitable for high-frequency applications. * **Q-Factor:** Generally ranges between 25 and 30, indicating low energy loss relative to energy stored. * **Rated Current (Idc):** Usually supports between 450mA to 800mA depending on the specific molding material. * **DC Resistance (DCR):** Low resistance (typically <0.50 Ω) to minimize heat dissipation. --- ### 3. Key Features and Applications #### Features: * **Molded Construction:** The "MC" in the prefix usually denotes a molded body which offers excellent mechanical strength and resistance to humidity/chemicals. * **High Reliability:** Designed to withstand the rigors of solder reflow processes. * **Wide Operating Temperature:** Typically rated from -40°C to +125°C. #### Common Applications: 1. **RF Decoupling:** Used to block high-frequency noise in communication equipment. 2. **Signal Filtering:** Used in band-pass or low-pass filters for telecommunications. 3. **DC/DC Converters:** Acts as an energy storage element in small power supply modules. 4. **Automotive Electronics:** Used in infotainment and sensor modules due to its rugged molded design. --- ### 4. Part Number Breakdown Guide If you are sourcing or replacing this part, here is how to read the code: ```text CT - MC - 1812 - R18 - K | | | | | Brand Type Size Value Tolerance (EIA) (0.18uH) (±10%) ```