The **CTX1-4P-R** is a high-performance, surface-mount (SMT) power inductor manufactured by Eaton (formerly Cooper Bussmann). It belongs to the **OCTA-PAC®** series, known for its versatility and toroidal construction. --- ## 1. Technical Specifications The "4P" in the part number indicates the specific size and power rating within the product family. | Parameter | Specification | | :--- | :--- | | **Inductance** | 1.13 µH | | **Current Rating (rms)** | 6.4 Amps | | **DCR (Direct Current Resistance)** | 0.0071 Ohms (Max) | | **Mounting Type** | Surface Mount (SMT) | | **Operating Temperature** | -40°C to +125°C | | **Package / Case** | Toroidal, Non-Standard SMT | | **Dimensions** | ~11.4mm x 11.4mm x 6.0mm | --- ## 2. Key Features The CTX1-4P-R is designed with specific mechanical and electrical characteristics to optimize power delivery: * **Toroidal Core Geometry:** Uses a ring-shaped core which inherently minimizes EMI (Electromagnetic Interference) because the magnetic flux is mostly contained within the core. * **Dual Winding Construction:** It features two separate windings that can be connected in **series** (to double the inductance) or in **parallel** (to double the current capacity). * **High Efficiency:** The low DCR (Direct Current Resistance) ensures minimal power loss through heat, making it suitable for high-efficiency DC-DC converters. * **Lead-Free/RoHS Compliant:** The "-R" suffix indicates that the part is RoHS compliant. --- ## 3. Common Applications Due to its high current handling and low noise profile, this part is typically found in: 1. **Buck/Boost Converters:** Used as the main energy storage element in voltage regulation. 2. **Input/Output Filters:** Used to smooth out ripples in power supplies. 3. **SEPIC Topologies:** The dual winding capability makes it ideal for Single-Ended Primary-Inductor Converters. 4. **Telecommunications:** Power modules for networking equipment where space and efficiency are critical. --- ## 4. Connection Configuration Because this inductor has **4 pads (4P)**, it can be utilized in two ways: * **Parallel Connection:** Connect pins 1-2 and 3-4 together. This provides the highest current rating and lowest inductance. * **Series Connection:** Connect pin 2 to pin 3. This increases the total inductance but decreases the maximum current rating.