BD241C NPN 3A 100V Silicon Power Transistor TO-220

BD241C NPN 3A 100V Silicon Power Transistor TO-220 is a general-purpose, high-power switching and amplification transistor engineered for medium-power applications in both consumer and industrial electronics. This robust NPN bi-polar junction transistor (BJT) features a collector current rating of 3 Amperes and a high collector-emitter breakdown voltage of 100 Volts. Consequently, the BD241C provides an excellent balance of voltage capability and current handling. Housed in the industry-standard TO-220 package, this device offers superior thermal dissipation compared to smaller transistors, which ensures stable performance even under sustained power loads. Therefore, designers frequently specify the BD241C when building reliable motor drivers, voltage regulators, and audio output stages, requiring a dependable workhorse component.

Key Features:

• High Power Rating: Rated for a continuous collector current (I_C) of 3A and a maximum collector-emitter voltage (V_CEO) of 100V, making it versatile for many power circuits.
• High Gain Linearity: Provides a DC current gain (h_FE) typically between 25 and 100, which simplifies drive circuitry while offering strong amplification.
• TO-220 Package: The rugged package is designed for easy mounting to a heatsink, furthermore maximizing thermal performance and reliability.
• Silicon Epitaxial Technology: Utilizes advanced silicon technology, ensuring low saturation voltage and fast switching speeds suitable for switching applications.
• General Purpose Use: Highly recommended for driver stages, series and shunt regulators, and low-frequency power amplifiers.

Technical Specifications:

• Transistor Type: NPN Bi-polar Junction Transistor (BJT)
• Collector Current (I_C): 3 A Maximum (Continuous)
• Collector-Emitter Voltage (V_CEO): 100 V Maximum
• Collector-Base Voltage (V_CBO): 100 V Maximum
• Emitter-Base Voltage (V_EBO): 5 V Maximum
• Total Power Dissipation (P_tot): 40 W (at T_C ≤ 25°C)
• DC Current Gain (h_FE): 25 to 100 (at I_C = 1.5 A, V_CE = 2 V)
• Transition Frequency (f_T): 3 MHz Minimum

Mechanical Specifications:

• Package Style: TO-220 (Plastic Pack)
• Mounting: Through-Hole, designed for heatsink attachment via the central mounting hole.
• Thermal Resistance (R_th(j-c)): 3.12 °C/W Max (Junction to Case)
• Flammability Rating: UL94 V-0

Dimensions:

• Body Height (excluding leads): ≈ 15.0 mm
• Body Width: ≈ 10.0 mm
• Lead Pitch (Between pins): 2.54 mm (0.1 inch)
• Mounting Hole Diameter: ≈ 3.8 mm
• Pin Length: ≈ 13.0 mm

Pinout and Wiring:

• Pin 1 (Base): Controls the current flow from collector to emitter. Connect your driving signal (current limiting resistor required) here.
• Pin 2 (Collector): The main current terminal. This is internally connected to the metal tab/heatsink mounting surface.
• Pin 3 (Emitter): The reference terminal, typically connected to the circuit ground or negative rail.
• Wiring Note: Always use an insulating thermal pad between the metal tab (Collector) and the heatsink if the heatsink is electrically grounded or shared with other components.

Datasheet Reference:

• Download BD241C NPN Power Transistor Datasheet

Commonly Used in:

• Power Supplies: Integrated into linear and switching regulators as series pass or switching elements.
• Audio Equipment: Frequently utilized in the output stage of Class B and complementary symmetry audio amplifiers.
• Motor Control: Driving DC motors, stepper motors, and solenoids requiring up to 3A of continuous current.

Applications:

• High-Current Switching: Switching medium-power loads, lights, and relays controlled by microcontrollers.
• Voltage Regulation: Forming the control element in high-current regulated power supplies.
• Power Amplification: Providing current gain in analog circuits, especially in the 3W to 10W power range.
• Driver Circuits: Used as the final power stage to drive MOSFETs or other high-current devices.

Equivalent Models:

• BD139: A lower power alternative, however, it features lower I_C and V_CEO limits.
• TIP31C: A popular, higher-current (5A) alternative in the same TO-220 package, often serving as a drop-in upgrade.
• 2SD1881: A common Japanese equivalent offering similar V_CEO and I_C ratings.

Package Includes:

• 1 x BD241C NPN 3A 100V Power Transistor (TO-220)