The part number **B65541-D-R33** refers to a high-quality **Ferrite Core** manufactured by **TDK Electronics (formerly EPCOS)**. Specifically, this part is an **RM8** (Rectangular Modul) core half, commonly used in high-frequency power supplies and telecommunications. --- ## 1. Technical Specifications Below are the primary physical and magnetic characteristics of the B65541-D-R33: | Parameter | Specification | | :--- | :--- | | **Core Shape** | RM8 (Rectangular Modul) | | **Material Grade** | N33 (Optimized for Power/Broadband) | | **$A_L$ Value** | Not specified (Usually defined by gap/material) | | **Effective Length ($l_e$)** | 38.4 mm | | **Effective Area ($A_e$)** | 64.0 mm² | | **Minimum Area ($A_{min}$)** | 55.0 mm² | | **Effective Volume ($V_e$)** | 2460 mm³ | | **Core Set Weight** | Approx. 12.0 g | --- ## 2. Key Components & Features ### Material: N33 The **N33** suffix indicates the ferrite material composition. - **Type:** MnZn (Manganese-Zinc) ferrite. - **Application:** Primarily used for **broadband transformers** and signal processing. - **Permeability:** It features high initial permeability ($\mu_i \approx 6000$), making it excellent for inductors that require high inductance in a small volume. ### Design: RM (Rectangular Modul) - **Space Efficiency:** The RM shape is designed to provide high packing density on Printed Circuit Boards (PCBs). - **Shielding:** The design offers self-shielding properties, reducing electromagnetic interference (EMI) with neighboring components. - **Pin Access:** It is compatible with standardized RM8 bobbins (usually 8 or 12 pins). --- ## 3. Applications The B65541 series is typically found in the following electronic circuits: 1. **Telecommunications:** High-stability filter inductors and broadband matching transformers. 2. **Power Conversion:** Small Switched-Mode Power Supplies (SMPS) and DC-DC converters. 3. **Signal Conditioning:** Used in ADSL/VDSL splitters and signal decoupling. --- ## 4. Ordering Note * **Core Halves:** This part number usually represents a **single core half**. For a complete functional transformer/inductor, you typically require two core halves, a bobbin (coil former), and a mounting clip (clamp). * **Gapping:** The "D" in the part number often signifies a specific mechanical version or a non-gapped (ungapped) version, meaning the user must specify the air gap if needed for energy storage. ---