The **UTD405L-TN3-R** is an N-channel enhancement mode Power MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) manufactured by **UTC (Unisonic Technologies Co., Ltd)**. It is designed for high-density, high-current switching applications. --- ### 1. Key Technical Specifications The following table outlines the fundamental electrical parameters of the UTD405L-TN3-R: | Parameter | Symbol | Maximum Rating | | :--- | :--- | :--- | | **Drain-Source Voltage** | $V_{DSS}$ | 30 V | | **Gate-Source Voltage** | $V_{GSS}$ | ±20 V | | **Continuous Drain Current** | $I_D$ | 18 A | | **Pulsed Drain Current** | $I_{DM}$ | 40 A | | **Static Drain-Source On-Resistance** | $R_{DS(ON)}$ | 28 mΩ (at $V_{GS}=10V$) | | **Total Power Dissipation** | $P_D$ | 30 W | | **Package Type** | TO-252 (DPAK) | Surface Mount | --- ### 2. Functional Description The UTD405L belongs to a class of MOSFETs optimized for low on-state resistance and fast switching. * **Logic Level Compatibility:** The "L" in the part number often signifies "Logic Level," meaning the MOSFET can be fully turned on with a relatively low gate voltage (typically 4.5V to 5V), making it compatible with microcontrollers. * **Packaging (TN3):** The TN3 suffix refers to the **TO-252** package (also known as DPAK). This is a surface-mount package designed for high power dissipation while maintaining a small footprint. * **Packing (R):** The "R" indicates that the parts are supplied on **Tape and Reel** for automated assembly. --- ### 3. Pin Configuration The TO-252 package typically follows this pinout standard: | Pin Number | Function | Description | | :--- | :--- | :--- | | **1** | **Gate (G)** | Controls the turning ON/OFF of the MOSFET. | | **2** | **Drain (D)** | Connected to the load (connected to the tab). | | **3** | **Source (S)** | Connected to the ground or negative supply. | --- ### 4. Common Applications Due to its low $R_{DS(ON)}$ and high current capacity, this part is commonly found in: * **DC-DC Converters:** For voltage regulation in power supplies. * **Motor Control:** Driving small to medium DC motors. * **Load Switches:** Used to turn power rails on/off in consumer electronics. * **Power Management:** Battery protection circuits and management systems.