BC639

Single Bipolar Transistors Overview

The onsemi BC639 is an NPN silicon medium power transistor housed in a TO-92 plastic package. It supports a maximum collector-emitter voltage of 80 V and a continuous collector current of 1 A. The device features a total device dissipation of 625 mW at 25°C ambient temperature, with a junction-to-ambient thermal resistance of 200 °C/W. Electrical characteristics include a minimum DC current gain (hFE) of 40 at 150 mA, a typical current-gain bandwidth product of 200 MHz, and a collector-emitter saturation voltage of 0.5 V at 500 mA. Operating temperatures range from -55°C to +150°C.

Single Bipolar Transistors Feature Summary

• High current capability supporting up to 1 A continuous collector current
• Low collector-emitter saturation voltage for efficient switching
• High current gain suitable for amplification applications

Single Bipolar Transistors Applications

• General-purpose amplifier circuits
• Switching applications requiring high current handling
• Audio frequency signal processing

Single Bipolar Transistors Procurement Notes

Verify the specific ordering suffix to confirm packaging type, such as bulk box or tape and reel quantities. Confirm RoHS compliance status by checking for the 'G' suffix designation. Ensure the voltage variant matches the application requirements, as the BC639 specifically denotes the 80 V rating distinct from other family members. Validate lead-free soldering compatibility if required by assembly standards.

Single Bipolar Transistors Selection Notes

Select the BC639 when an NPN transistor requires 80 V breakdown voltage and 1 A current capacity within a TO-92 form factor. Compare against BC635 (45 V) and BC637 (60 V) variants to ensure voltage ratings meet circuit demands. Consider the thermal resistance and power dissipation limits for heat management in enclosed designs. Verify hFE binning requirements if precise gain control is necessary for the specific amplifier stage.

Single Bipolar Transistors Part Context

The BC639 belongs to the BC63x series of NPN silicon transistors manufactured by onsemi. This series includes complementary PNP devices such as the BC640. The components are designed for general-purpose high-current applications and share similar physical dimensions and pinouts, facilitating design flexibility across different voltage ratings within the same package style.

Single Bipolar Transistors Replacement Considerations

Direct substitutes include the BC639-16 for higher voltage ratings (120 V). Complementary PNP equivalents in the same series are the BC640. Other manufacturers produce pin-compatible NPN transistors with matching 80 V and 1 A specifications, provided thermal and electrical parameters align with the original design constraints.