BC449

Single Bipolar Transistors Overview

The onsemi BC449 is a general-purpose NPN silicon epitaxial planar transistor housed in a TO-92 (TO-226AA) three-pin package. It features a maximum collector-emitter voltage of 45V and a continuous collector current rating of 100mA, with a maximum power dissipation of 500mW. The device offers a DC current gain (hFE) range typically between 110 and 800 at a collector current of 2mA and Vce of 5V. Its transition frequency is specified at 300MHz, supporting operation up to a junction temperature of 150°C.

Single Bipolar Transistors Feature Summary

• General-purpose NPN switching and amplification capability
• Low noise performance suitable for sensitive signal processing
• Complementary pairing available within the BC546-BC550 series

Single Bipolar Transistors Applications

• General purpose amplifier circuits
• Switching applications
• Audio pre-amplifier stages

Single Bipolar Transistors Procurement Notes

Verify component authenticity through authorized distribution channels due to potential availability from multiple manufacturers. Confirm RoHS compliance status as specifications may vary by production lot or region. Check datasheet revisions for any updates to absolute maximum ratings or thermal characteristics before final integration into designs.

Single Bipolar Transistors Selection Notes

Select this component when a standard NPN transistor with moderate voltage handling and low noise characteristics is required. Ensure the application current remains within the 100mA limit and that heat dissipation requirements fit the TO-92 package constraints. Consider complementary PNP variants if push-pull configurations are needed.

Single Bipolar Transistors Part Context

The BC449 belongs to the widely used BC546-BC550 family of NPN transistors produced by onsemi. This series is characterized by its versatility in consumer electronics and industrial control systems. The BC449 specifically provides a standardized gain bin, ensuring predictable performance across mass-produced devices compared to unsorted general-purpose alternatives.

Single Bipolar Transistors Replacement Considerations

Direct substitutes include other members of the BC546-BC550 series such as BC547 or BC548, provided their specific gain ranges match the design requirements. Verify pinout compatibility and thermal resistance values when considering cross-manufacturer equivalents.