The **HMU1055-R56** is a high-current, surface-mount (SMD) power inductor commonly used in DC-DC converter applications. It is designed for high-frequency power supplies where efficiency and compact size are critical. --- ### 1. Technical Specifications The part number itself reveals key characteristics of the component. Below are the typical specifications for the HMU1055-R56: | Parameter | Value | | :--- | :--- | | **Inductance** | 0.56 µH (indicated by "R56") | | **Inductance Tolerance** | Usually ±20% | | **Saturation Current (Isat)** | ~25A to 40A (varies by specific series) | | **DC Resistance (DCR)** | Very Low (typically < 2 mΩ) | | **Operating Temperature** | -40°C to +125°C | | **Package Size** | Approx. 10.0 x 5.0 x 5.0 mm | --- ### 2. Physical Construction The HMU series is typically built using a **molded powder iron core** or a specialized ferrite structure. Key features include: * **Shielded Design:** The inductor is magnetically shielded to minimize Electromagnetic Interference (EMI) with surrounding components. * **Flat Wire Technology:** Many high-current inductors in this class use flat copper wire instead of round wire. This reduces the "skin effect" and lowers DC resistance, allowing for higher efficiency. * **SMD Terminations:** Features robust solder pads designed to handle high vibrations and thermal cycling. --- ### 3. Key Electronic Functions In a circuit, the HMU1055-R56 serves several critical roles: 1. **Energy Storage:** In switching regulators (Buck/Boost converters), it stores energy in its magnetic field during the "on" cycle and releases it during the "off" cycle. 2. **Current Smoothing:** It acts as a low-pass filter, smoothing out the ripple current from the switching power supply to provide a steady DC output. 3. **Noise Suppression:** It prevents high-frequency noise from traveling back into the power source or forward into sensitive loads. --- ### 4. Common Applications Due to its high current handling and low profile, you will find this part in: * **Graphics Cards (GPUs):** Powering the core voltage rails. * **Motherboards:** VRM (Voltage Regulator Module) circuits for CPUs. * **Servers:** High-efficiency power distribution units. * **Industrial Power Supplies:** DC-DC modules requiring high power density. ---