The **2SC1384-X-AB3-R** is an NPN epitaxial silicon transistor designed primarily for low-frequency power amplification and driver-stage applications. It is commonly used in audio equipment, signal switching, and voltage regulation circuits. --- ### 1. General Specifications The part number can be broken down to understand its characteristics (UTC - Unisonic Technologies naming convention): * **2SC1384**: The base transistor model (NPN). * **X**: The Rank/HFE (Gain) classification. * **AB3**: Indicates the package type (**SOT-89**). * **R**: Indicates Tape & Reel packaging. | Parameter | Symbol | Value | Unit | | :--- | :--- | :--- | :--- | | **Collector-Base Voltage** | $V_{CBO}$ | 60 | V | | **Collector-Emitter Voltage** | $V_{CEO}$ | 50 | V | | **Emitter-Base Voltage** | $V_{EBO}$ | 5 | V | | **Collector Current (DC)** | $I_{C}$ | 1.0 | A | | **Collector Dissipation ($T_a=25°C$)** | $P_{C}$ | 500 | mW | | **Junction Temperature** | $T_{J}$ | +150 | °C | --- ### 2. Electrical Characteristics The "X" classification refers to the DC Current Gain ($h_{FE}$) range. | Characteristic | Symbol | Test Conditions | Min | Max | Unit | | :--- | :--- | :--- | :--- | :--- | :--- | | **DC Current Gain** | $h_{FE}$ | $V_{CE}=10V, I_{C}=150mA$ | 85 | 340 | - | | **Collector Cut-off Current** | $I_{CBO}$ | $V_{CB}=20V, I_{E}=0$ | - | 0.1 | µA | | **Saturation Voltage** | $V_{CE(sat)}$ | $I_{C}=500mA, I_{B}=50mA$ | - | 0.4 | V | | **Transition Frequency** | $f_{T}$ | $V_{CE}=10V, I_{C}=50mA$ | 200 | - | MHz | --- ### 3. Pinout Configuration (SOT-89) The AB3 package (SOT-89) is a surface-mount package with high thermal efficiency. | Pin Number | Designation | Function | | :--- | :--- | :--- | | 1 | **Base** | Controls the bias of the transistor | | 2 | **Collector** | Connected to the heat sink/tab; primary current outlet | | 3 | **Emitter** | Primary current inlet | --- ### 4. Typical Applications * **Audio Power Amplifier**: Used in the driver stage to amplify low-level signals before the final output stage. * **Voltage Regulation**: Acts as a pass transistor in linear power supplies. * **Relay/Solenoid Driver**: Because it supports up to 1A of collector current, it can easily drive small inductive loads. * **General Purpose Switching**: High-speed switching in digital-to-analog interfaces. --- ### 5. Equivalent/Complementary Parts * **Complementary PNP Pair**: 2SA684 (Used for push-pull amplifier configurations). * **Equivalent Models**: BC337, 2N2222 (Note: check pinouts and power ratings as they may differ slightly).