BC857A-HF

Overview

The BC857A-HF is a PNP silicon bipolar junction transistor manufactured by Comchip Technology. It is housed in an SOT-23-3 surface-mount package and operates within a temperature range of -65°C to +150°C. Key electrical specifications include a maximum collector-emitter voltage (VCEO) of -30 V, a collector-base voltage (VCBO) of -30 V, and an emitter-base voltage (VEBO) of -5 V. The device supports a continuous collector current of 100 mA with a power dissipation rating of 250 mW. DC current gain (hFE) for the 'A' grade ranges from 420 to 800, ensuring high amplification capabilities.

Feature Summary

• High DC current gain suitable for sensitive signal amplification
• Halogen-free construction compliant with environmental standards
• Designed for general-purpose switching and linear applications

Applications

• General-purpose signal amplification circuits
• Electronic switching applications
• Complementary pairs with NPN transistors

Procurement Notes

Verify the specific hFE binning requirements against your circuit design needs, as the 'A' suffix denotes a specific gain range. Confirm that the SOT-23-3 footprint matches your PCB layout. Ensure the halogen-free certification aligns with your project's regulatory compliance standards before finalizing procurement.

Selection Notes

Select this component when a PNP transistor with high current gain is required in a compact SMD form factor. The -30 V voltage rating limits its use in low-voltage logic or analog stages rather than high-voltage power switching. Consider thermal management for the 250 mW dissipation limit in enclosed designs.

Part Context

This part belongs to the BC857 series of PNP silicon transistors. It serves as a complementary device to NPN counterparts like the BC847 series. The 'HF' suffix indicates a halogen-free formulation, while 'A' specifies the high-gain binning class, distinguishing it from lower gain variants in the same family.

Replacement Considerations

Compatible substitutes include other manufacturers' BC857A devices in SOT-23 packages, such as those from Diodes Incorporated or Nexperia, provided they meet the identical -30 V and 100 mA ratings.