The **2SC4236** is a high-voltage, high-speed switching NPN power transistor. It is primarily designed for use in power supplies and horizontal deflection output circuits. --- ### 1. Key Technical Specifications The following table summarizes the absolute maximum ratings and electrical characteristics for the 2SC4236: | Parameter | Symbol | Rating | Unit | | :--- | :--- | :--- | :--- | | Collector-Base Voltage | $V_{CBO}$ | 1200 | V | | Collector-Emitter Voltage | $V_{CEO}$ | 800 | V | | Emitter-Base Voltage | $V_{EBO}$ | 7 | V | | Collector Current (DC) | $I_C$ | 6 | A | | Collector Current (Pulse) | $I_{CP}$ | 12 | A | | Collector Power Dissipation | $P_C$ | 100 | W | | Junction Temperature | $T_j$ | 150 | °C | --- ### 2. Physical and Structural Features The 2SC4236 typically comes in a **TO-3P** or **TO-247** package, which is designed for through-hole mounting on a PCB. Because of its high power dissipation (100W), it requires a substantial **heatsink** to prevent thermal runaway. * **Type:** NPN Silicon Triple Diffused Transistor. * **Pinout Configuration:** 1. **Base (B)** 2. **Collector (C)** 3. **Emitter (E)** --- ### 3. Primary Applications Due to its high voltage tolerance and fast switching speeds, the 2SC4236 is commonly found in the following circuits: * **Switch-Mode Power Supplies (SMPS):** Used as the main switching element to convert DC voltages at high frequencies. * **Horizontal Deflection:** Historically used in CRT monitors and televisions to control the electron beam. * **High-Voltage Inverters:** Used in industrial lighting or motor control where high voltage spikes are common. * **Power Amplifiers:** Specifically in high-voltage industrial applications. --- ### 4. Comparison with Equivalent Parts If the 2SC4236 is unavailable, the following transistors are often considered equivalents, though parameters should always be verified against the specific circuit requirements: | Equivalent Part | $V_{CEO}$ | $I_C$ | Package | | :--- | :--- | :--- | :--- | | **2SC4458** | 800V | 7A | TO-3P | | **BUH515** | 700V | 8A | TO-247 | | **KSC5027** | 800V | 3A | TO-220 (Lower Power) | --- ### 5. Implementation Example (Simple Switch) To use this NPN transistor as a switch, the Base must be driven with sufficient current to saturate the collector-emitter path. ```cpp // Example: Calculating Base Resistor (Rb) // Rb = (V_control - V_be) / I_b // Where I_b is usually 1/5th to 1/10th of I_c for full saturation. ```