### Overview of the CTX15-4P-R The **CTX15-4P-R** is a high-performance, surface-mount (SMT) power inductor/transformer manufactured by **Eaton (formerly Coiltronics)**. It belongs to the **OCTA-PAC®** series, known for its versatile design featuring two separate windings that can be connected in several configurations. --- ### Technical Specifications The following table outlines the key electrical and physical characteristics of the CTX15-4P-R: | Parameter | Specification | | :--- | :--- | | **Inductance (Parallel)** | 14.3 µH (approx. 15 µH nominal) | | **Inductance (Series)** | 57.2 µH | | **Current Rating (Isat)** | ~3.1 A (Parallel) | | **DC Resistance (DCR)** | ~0.043 Ω (Parallel) | | **Configuration** | 2 Windings (Dual Coil) | | **Operating Temperature** | -40°C to +125°C | | **Mounting Type** | Surface Mount (SMT) | | **Package Size** | OCTA-PAC Plus (Size 4) | --- ### Core Features and Construction 1. **Dual Winding Design:** The device consists of two identical windings. This allows the user to configure the part as: * **Single Inductor:** Windings in series or parallel. * **1:1 Transformer:** Primary and secondary isolation. * **Common Mode Choke:** For EMI filtering. 2. **Magnetic Shielding:** The toroidal core design inherently provides low EMI (Electro-Magnetic Interference), making it suitable for noise-sensitive environments. 3. **High Power Density:** The "Plus" designation indicates the use of higher-grade materials (typically powder iron or specialized ferrite) to handle higher peak currents without saturating. --- ### Common Applications The CTX15-4P-R is frequently used in power conversion circuits including: * **Buck/Boost Converters:** As the main energy storage inductor. * **SEPIC Converters:** Utilizing both windings for coupled inductance. * **Flyback Transformers:** For low-power isolated DC-DC conversion. * **Filtering:** Acting as a common-mode or differential-mode choke in power supplies. --- ### Wiring Configurations | Type | Connection | Result | | :--- | :--- | :--- | | **Parallel** | Pins (1-2) connected to (4-3) | Higher Current, Lower Inductance (L) | | **Series** | Pin 2 connected to Pin 4 | Lower Current, Higher Inductance (4L) | | **Transformer**| Input on 1-2, Output on 4-3 | 1:1 Turns Ratio |