BC817-40

Overview

The BC817-40 is a single NPN bipolar junction transistor manufactured by Diotec Semiconductor, distributed by Shenzhen SLKORMicro Semicon Co., Ltd. It features a maximum collector-emitter voltage of 45 V and a continuous collector current of 800 mA. The device operates with a transition frequency of 100 MHz and dissipates up to 310 mW of power. Key electrical characteristics include a DC current gain (hFE) of at least 250 at 100 mA and 1 V, and a saturation voltage of 700 mV at 50 mA base and 500 mA collector currents. It is housed in an SOT-23-3 surface-mount package.

Feature Summary

• NPN configuration optimized for general-purpose switching and amplification applications
• High DC current gain ensures efficient signal control with minimal base drive requirements
• Robust thermal performance supports operation across extended temperature ranges

Applications

• General-purpose switching circuits
• Amplifier stages in consumer electronics
• Interface logic level translation

Procurement Notes

Verify the manufacturer marking on the component body to confirm Diotec Semiconductor origin, as Shenzhen SLKORMicro Semicon Co., Ltd. acts as a distributor. Ensure the part number suffix matches the specific hFE binning grade required for your design. Cross-reference the datasheet revision date to confirm compliance with current RoHS3 standards before finalizing procurement orders.

Selection Notes

Select this component when a compact NPN transistor with moderate voltage handling and high current gain is required. The SOT-23-3 package suits space-constrained printed circuit board layouts. Compare the hFE minimum value against circuit requirements to ensure adequate drive capability. Consider the thermal dissipation limits relative to the expected operating current density in the final assembly.

Part Context

This component belongs to the BC817 family of small-signal NPN transistors. The -40 suffix typically denotes a specific DC current gain binning range, distinguishing it from other variants like the BC817-25. These devices are widely used in low-power electronic designs where reliable switching and amplification are necessary within standard commercial temperature ranges.

Replacement Considerations

Consult official cross-reference lists for equivalent parts from other manufacturers. Verify that any substitute maintains identical pinout configurations and meets or exceeds the original voltage, current, and gain specifications.