Litz wire is a specialized type of conductor engineered to minimize power losses at high frequencies, a challenge known as the “skin effect” and “proximity effect.” Unlike a solid core, Litz wire is constructed from multiple thin, individually insulated strands that are twisted or woven together in a precise, controlled pattern. This unique structure defines its performance and primary applications.

The classification of Litz wire is primarily based on its construction and the frequency range it is designed to address. It is categorized by key parameters such as the **number of strands**, the **diameter of each strand**, and the **twisting pattern** (e.g., bunching, braiding). More strands and finer gauges are used for higher frequency operations. Additionally, Litz wire can be grouped by its **overall insulation** (silk, nylon, or heavy-duty formal) and its intended application environment, such as for high-voltage windings or medical devices requiring biocompatible coatings.

The defining purpose of Litz wire is to maintain low AC resistance (Rac) in high-frequency electromagnetic fields. By ensuring that each strand occupies all possible positions within the cross-section of the cable over a given length, current is distributed evenly across the entire conductive area. This drastically reduces losses compared to a solid conductor. Consequently, Litz wire is indispensable in high-efficiency applications. Its primary uses include the windings of **high-frequency transformers and inductors** in switch-mode power supplies (SMPS) and RF circuits, **resonant coils** for wireless charging systems and induction heating, and the **primary windings** of high-Q factor inductors. It is also critical in the **pickup coils** of sensitive medical imaging equipment like MRI machines. In essence, Litz wire is the material of choice where efficient power transfer at frequencies from tens of kilohertz to several megahertz is paramount, enabling advancements in power electronics, telecommunications, and medical technology.