The **CPL-4-50TR-R** is a specific surface-mount electronic component, primarily known as a **Directional Coupler** manufactured by **Eaton** (formerly Cooper Bussmann). It is widely used in high-frequency applications to sample or monitor power signals. --- ### 1. Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Component Type** | Directional Coupler | | **Frequency Range** | Up to 1.0 GHz (Commonly used in Sub-GHz RF) | | **Coupling Value** | 13 dB (Typical) | | **Insertion Loss** | Low (approx. 0.2 dB to 0.5 dB) | | **Impedance** | 50 Ohms | | **Mounting Type** | Surface Mount (SMD/SMT) | | **Packaging** | Tape and Reel (TR) | --- ### 2. Functional Description A directional coupler like the CPL-4-50TR-R is a 4-port passive device used to couple a specific amount of electromagnetic power from one transmission line to another. * **Main Path:** The signal travels from the Input port to the Output port with minimal loss (Insertion Loss). * **Coupled Path:** A small fraction of the power (determined by the coupling factor, e.g., 13dB) is diverted to the Coupled port. * **Isolation:** It ensures that signals traveling in the reverse direction do not reach the coupled port, allowing for "directional" measurement. --- ### 3. Physical & Material Composition * **Construction:** These are often built using **Inductor-based** technology (wire-wound on a ceramic or ferrite core) rather than microstrip lines to save space on the PCB. * **Termination:** Lead-free, RoHS compliant construction. * **Small Footprint:** Designed for high-density circuit boards found in telecommunications. --- ### 4. Common Applications 1. **Power Monitoring:** Measuring the output power of a radio transmitter without interrupting the main signal flow. 2. **SWR Measurement:** Determining the Standing Wave Ratio to check antenna impedance matching. 3. **Signal Sampling:** Taking a small sample of a signal for feedback loops or frequency counters. 4. **Distribution Networks:** Splitting signals in cable TV (CATV) or wireless infrastructure. --- ### 5. Part Number Breakdown * **CPL:** Coupler series. * **4:** Designates the number of ports/physical configuration. * **50:** Typically refers to the characteristic impedance (50 $\Omega$). * **TR:** Tape and Reel packaging (standard for automated pick-and-place). * **R:** RoHS compliant.