## Overview of the 2SC4322 Transistor The **2SC4322** is a high-speed, high-voltage NPN Silicon Epitaxial Planar Transistor. It is primarily designed for high-resolution color display horizontal deflection output and high-speed switching applications. --- ### 1. Key Technical Specifications Below are the absolute maximum ratings and electrical characteristics typically found in the datasheet: | Parameter | Symbol | Maximum Rating | Unit | | :--- | :--- | :--- | :--- | | Collector-Base Voltage | $V_{CBO}$ | 1500 | V | | Collector-Emitter Voltage | $V_{CEO}$ | 800 | V | | Emitter-Base Voltage | $V_{EBO}$ | 6 | V | | Collector Current (DC) | $I_C$ | 12 | A | | Collector Current (Pulse) | $I_{CP}$ | 30 | A | | Total Power Dissipation ($T_c = 25^\circ C$) | $P_C$ | 150 | W | | Junction Temperature | $T_j$ | 150 | $^\circ C$ | --- ### 2. Pin Configuration The 2SC4322 is usually housed in a **TO-3PL** (or similar large-scale) package to handle high power dissipation. | Pin Number | Terminal Name | Description | | :--- | :--- | :--- | | 1 | **Base** | Controls the flow of current between Collector and Emitter | | 2 | **Collector** | Connected to the load (High Voltage) | | 3 | **Emitter** | Usually connected to the ground/common | --- ### 3. Key Features * **High Speed:** Optimized for fast switching transitions, reducing energy loss during state changes. * **High Breakdown Voltage:** Withstands up to 1500V, making it suitable for CRT (Cathode Ray Tube) circuits. * **High Reliability:** Designed to operate under the thermal stress of industrial or display power supplies. * **Saturation Voltage:** It features a low collector-emitter saturation voltage ($V_{CE(sat)}$), which improves efficiency. --- ### 4. Common Applications * **Horizontal Deflection:** Used in high-resolution monitors and color TVs to drive the deflection yoke. * **Switching Regulators:** Acts as a power switch in high-voltage Switch Mode Power Supplies (SMPS). * **Industrial Converters:** Suitable for DC-DC converters requiring high voltage handling. --- ### 5. Equivalent/Replacement Parts If the 2SC4322 is unavailable, the following transistors are often considered as functional equivalents (always verify pinouts and thermal specs): * **2SC3896** * **2SC5296** * **BU2520DX** (Note: Some versions include an internal damper diode)