The **CTX25-2P-R** is a high-performance, dual-winding toroidal inductor manufactured by **Eaton (formerly Coiltronics)**. It belongs to the **OCTA-PAC®** series, which is widely recognized for its versatility in power conversion applications. --- ### 1. Key Technical Specifications Below are the primary electrical and physical characteristics of the CTX25-2P-R: | Feature | Specification | | :--- | :--- | | **Inductance (Parallel)** | 24.6 µH | | **Inductance (Series)** | 98.4 µH | | **Current Rating (Irms)** | 1.81 A (Parallel) | | **DC Resistance (DCR)** | 0.081 Ω (Max) | | **Operating Temperature** | -40°C to +125°C | | **Mounting Type** | Surface Mount (SMD) | | **Termination** | RoHS Compliant (Lead-Free) | --- ### 2. Functional Design The "2P" in the part number signifies that it features **dual windings**. This provides engineers with three configuration options depending on how the pins are connected on the PCB: 1. **Parallel Mode:** Increases the current-carrying capacity while keeping inductance low. 2. **Series Mode:** Increases the total inductance (4x the single winding) for better filtering. 3. **1:1 Transformer Mode:** Can be used as a flyback transformer or for isolation between two circuits. --- ### 3. Core Materials and Construction * **Toroidal Geometry:** The doughnut-shaped core naturally contains the magnetic flux, resulting in very low **Electromagnetic Interference (EMI)**. This makes it ideal for noise-sensitive environments. * **Powder Iron Core:** This material offers high saturation flux density, meaning the component can handle high peak currents without the inductance "dropping off" abruptly. * **Encapsulation:** The part is typically housed in a rugged base with a flat top for high-speed automated "pick and place" assembly. --- ### 4. Common Applications Due to its high power density and dual-winding flexibility, the CTX25-2P-R is commonly found in: * **DC-DC Converters:** Used in Buck, Boost, and SEPIC topologies. * **Switch Mode Power Supplies (SMPS):** Acts as an output filter inductor. * **Signal Isolation:** Provides 1:1 coupling for data or power lines. * **Computer Peripherals:** Power management for servers and high-end workstations. --- ### 5. Part Number Breakdown ```text CTX 25 - 2P - R | | | | | | | +-- RoHS Compliant | | +------ Size Code (OCTA-PAC series 2) | +----------- Inductance Value Code +--------------- Product Series (Coiltronics Toroidal) ```