BC858B

Overview

The Diotec Semiconductor BC858B is a surface-mount general-purpose PNP bipolar junction transistor (BJT) housed in an SOT-23 package. It features a maximum collector-emitter voltage of 45 V and a continuous DC collector current of -100 mA, with a total power dissipation rating of 300 mW at 25°C ambient temperature. The device offers three distinct DC current gain groups: Group A (hFE min 90), Group B (hFE min 150), and Group C (hFE min 270). Electrical characteristics include a transition frequency of 100 MHz, a collector-base cutoff current of 15 nA, and a base-emitter saturation voltage of up to 900 mV under specified conditions.

Feature Summary

• General-purpose design suitable for signal processing, switching, and amplification applications
• Available in three standardized DC current gain groups (A, B, and C) for flexible circuit design
• Compliant with RoHS directives without exemptions and REACH regulations

Applications

• Signal processing circuits
• Electronic switching applications
• Amplifier stages

Procurement Notes

Verify the specific ordering suffix when purchasing. The absence of a suffix indicates industrial grade availability. Suffixes such as -C denote commercial grade, while -Q and -AQ indicate AEC-Q101 compliance or qualification respectively. Confirm that the requested variant matches the required reliability standard for the intended application environment before finalizing orders.

Selection Notes

Select the appropriate current gain group based on circuit requirements. Group A provides a minimum hFE of 90, Group B ensures a minimum of 150, and Group C guarantees a minimum of 270. Ensure the operating voltage does not exceed the 45 V collector-emitter limit. Consider thermal resistance values when designing for high ambient temperatures or limited PCB copper pad areas to maintain safe junction temperatures.

Part Context

This component belongs to the Diotec BC856 through BC860 series of universal PNP transistors. These devices are designed as complementary counterparts to NPN transistors within the same family, such as the BC846 through BC850 series. The series utilizes standard small-outline packages like SOT-23 and TO-236AB, providing a versatile solution for general electronic designs requiring matched or interchangeable PNP switching and amplification capabilities.

Replacement Considerations

BC858B

FAQ

What are the available DC current gain groups for the BC858B?

The BC858B is available in three current gain groups: Group A (minimum hFE of 90), Group B (minimum hFE of 150), and Group C (minimum hFE of 270).

How does the suffix affect the product specification?

The suffix determines the quality grade. No suffix indicates industrial grade, -C denotes commercial grade, -Q signifies AEC-Q101 compliance, and -AQ indicates AEC-Q101 qualification.

What is the maximum power dissipation rating?

The maximum total power dissipation is rated at 300 mW when mounted on a printed circuit board with the minimum recommended pad layout at an ambient temperature of 25°C.