## Technical Overview of the UP4B-220-R The **UP4B-220-R** is a high-power, shielded drum core inductor part of the **Uni-Pac (UP)** series, originally manufactured by Coiltronics (now part of **Eaton Bussmann**). It is specifically designed for high-density power applications. ### 1. Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Inductance** | 22.0 µH | | **Tolerance** | ±20% | | **Current Rating (Irms)** | 5.3 Amps | | **Saturation Current (Isat)** | 8.0 Amps | | **DC Resistance (DCR)** | 0.0232 Ohms (Max) | | **Operating Temperature** | -40°C to +125°C | | **Package / Case** | Surface Mount (SMD) | --- ### 2. Core Components and Materials The construction of the UP4B-220-R involves several critical electronic material features: * **Ferrite Drum Core:** The "brain" of the inductor. It uses a high-permeability ferrite material to store energy in the form of a magnetic field. * **Magnetic Shielding:** The "4B" designation indicates a shielded design. This involves a ferrite sleeve surrounding the winding to minimize **Electromagnetic Interference (EMI)**, ensuring it doesn't interfere with nearby sensitive components on the PCB. * **Windings:** Utilizes heavy-gauge copper wire to achieve very low DC resistance (DCR), which minimizes heat generation and maximizes efficiency. * **Lead-Free Construction:** The "-R" suffix indicates that the part is **RoHS compliant**, meaning it is free from lead and other hazardous substances. --- ### 3. Application Use Cases Because of its high current handling and compact SMD footprint, it is typically found in: 1. **DC-DC Converters:** Acts as an energy storage element in buck, boost, or buck-boost regulators. 2. **Power Supplies:** Used for input/output filtering to smooth out voltage ripples. 3. **Industrial Electronics:** Found in motor drives and high-power LED drivers. 4. **Telecommunications:** Distributed power systems where EMI shielding is critical. --- ### 4. Comparison: UP4B vs. Standard Inductors * **Higher Power Density:** The Uni-Pac design allows for a much higher current-to-size ratio than traditional molded inductors. * **Thermal Stability:** Designed to operate at high temperatures (up to 125°C) without significant degradation in inductance.