The part number **B65735-J-R87** refers to a high-performance **Ferrite Core** manufactured by **TDK Electronics (formerly EPCOS)**. Specifically, this part is an **ER 35/21/11 core** made from **N87 material**. Below is a detailed breakdown of its specifications and electronic properties. ### 1. Technical Specifications | Property | Value / Description | | :--- | :--- | | **Manufacturer** | TDK Electronics (EPCOS) | | **Core Shape** | ER (E-Round) Core | | **Material Grade** | N87 (Power Material) | | **Core Size** | 35 mm (Width) x 21 mm (Height) x 11 mm (Depth) | | **Magnetic Path Length ($l_e$)** | 89.6 mm | | **Effective Area ($A_e$)** | 107 $mm^2$ | | **Effective Volume ($V_e$)** | 9590 $mm^3$ | | **Initial Permeability ($\mu_i$)** | 2200 ± 25% | --- ### 2. Material Properties: N87 The **N87** material is a Manganese-Zinc (MnZn) ferrite designed primarily for power applications. Its characteristics include: * **Frequency Range:** Optimized for power transformers operating up to approximately **500 kHz**. * **Low Core Loss:** It is engineered for low power dissipation, particularly at temperatures around **100°C**, which is the typical operating point for power electronics. * **Saturation Flux Density:** High saturation induction (approx. 490 mT at 25°C), making it suitable for high-power density designs. --- ### 3. Core Design (ER Shape) The **ER (E-Round)** shape is a hybrid between a standard E-core and a Pot core. * **Round Center Post:** The "R" in ER signifies a round center limb. This is beneficial because it allows for easier winding of copper wire (especially thick wire or litz wire) and reduces the length of the turn, which lowers **DC resistance (DCR)**. * **Compact Footprint:** It provides a good balance between volume, winding area, and surface area for heat dissipation. --- ### 4. Common Applications Due to its N87 power material and ER shape, this part is commonly used in: 1. **Switch-Mode Power Supplies (SMPS):** Main transformers or output chokes. 2. **DC-DC Converters:** High-frequency power conversion in automotive or industrial settings. 3. **Inductors:** Storage or filter inductors requiring high energy storage. 4. **Telecommunications:** Power modules requiring compact magnetic components. --- ### 5. Accessory Information To use the B65735-J-R87 core, you typically need two core halves (the part number usually refers to one half) and a corresponding bobbin (coil former). ```markdown Typical Accessories: - Bobbin Part Number: B65736 (available in horizontal or vertical SMD/THT) - Yoke/Clips: For mechanical fastening of the two core halves. ``` ---