The **2SD1875L-R-T92-R** is an NPN epitaxial silicon transistor. It is primarily designed for low-frequency power amplification and general-purpose switching applications. --- ### 1. Key Technical Specifications The following table highlights the absolute maximum ratings and electrical characteristics for this specific part: | Parameter | Symbol | Maximum Rating / Value | | :--- | :--- | :--- | | **Collector-Base Voltage** | $V_{CBO}$ | 60V | | **Collector-Emitter Voltage** | $V_{CEO}$ | 50V | | **Emitter-Base Voltage** | $V_{EBO}$ | 5V | | **Collector Current (DC)** | $I_C$ | 3A | | **Collector Dissipation** | $P_C$ | 750mW | | **DC Current Gain** | $h_{FE}$ | 120 ~ 560 (Range varies by rank) | | **Transition Frequency** | $f_T$ | 120 MHz (Typical) | --- ### 2. Part Number Breakdown The suffixing in UTC (Unisonic Technologies) parts provides specific details about the manufacturing and packaging: * **2SD1875**: The base model number (NPN Transistor). * **L**: Lead-free / RoHs Compliant. * **R**: Refers to the $h_{FE}$ (Gain) classification. "R" typically denotes a specific gain range (e.g., 180-390). * **T92**: Indicates the **TO-92** package type (a small plastic package with three leads). * **R**: The final 'R' usually denotes the packing type, such as **Tape Reel**. --- ### 3. Pin Configuration For the TO-92 package, the pinout is generally as follows (looking at the flat side): 1. **Emitter (E)** 2. **Collector (C)** 3. **Base (B)** --- ### 4. Typical Applications Due to its high collector current ($3A$) relative to its small size, it is commonly used in: * **Voltage Regulators:** Acting as a pass transistor. * **Relay Drivers:** Switching medium-power loads. * **Audio Amplifiers:** Used in the output stage of small portable audio devices. * **DC-DC Converters:** Low power switching cycles. ---