The **CTX1-4-R** is a high-performance, surface-mount (SMT) power inductor/transformer belonging to the **OCTA-PAC®** series, originally manufactured by Coiltronics (now part of **Eaton Bussmann**). --- ### 1. Technical Specifications The "1-4" in the part number designates the specific size and winding configuration. Below are the key electrical characteristics: | Parameter | Specification | | :--- | :--- | | **Inductance (Parallel)** | 1.15 µH ±20% | | **Inductance (Series)** | 4.60 µH ±20% | | **Isat (Saturation Current)** | 10.4 A (Parallel) | | **Irms (Heating Current)** | 4.80 A (Parallel) | | **DCR (DC Resistance)** | 0.0162 Ω (Parallel) | | **Operating Temperature** | -40°C to +125°C | --- ### 2. Physical Construction & Features * **Dual Winding Design:** It consists of two identical windings that can be connected in **series** or **parallel**. * **Toroidal Core:** Uses a powdered iron toroidal core, which offers low EMI (Electromagnetic Interference) and high efficiency. * **Surface Mount:** Designed for pick-and-place automation with a rugged, low-profile header. * **"R" Suffix:** Indicates that the part is **RoHS compliant** (lead-free). --- ### 3. Applications and Use Cases Because of its dual-winding nature, the CTX1-4-R is highly versatile: 1. **Buck/Boost Converters:** Used as a standard power inductor for DC-DC conversion. 2. **SEPIC Topology:** Ideal for Single-Ended Primary-Inductor Converters where two coupled inductors are required. 3. **1:1 Transformers:** Can be used as an isolation transformer or for voltage doubling/halving. 4. **Common Mode Choke:** Effective for filtering noise in power lines when wired appropriately. --- ### 4. Comparison: Series vs. Parallel Wiring When integrating this part into a PCB layout, the wiring configuration changes the performance: ```markdown # Parallel Connection (Pin 1-4, Pin 2-3 tied) - Higher Current Capacity (Isat) - Lower Inductance - Lower Resistance (DCR) # Series Connection (Pin 2-3 tied together) - Lower Current Capacity - 4x Inductance (Relative to parallel) - Higher Resistance (DCR) ```