BC849BW

Overview

The BC849BW is a single NPN general-purpose bipolar junction transistor manufactured by Taiwan Semiconductor Corporation. It utilizes silicon epitaxial planar technology and is housed in the SOT-323 surface-mount package. The device supports a maximum collector current of 100 mA and a collector-emitter voltage of 30 V. Key electrical characteristics include a DC current gain (hFE) ranging from 200 to 450, a transition frequency of 100 MHz, and a power dissipation rating of 200 mW. It operates within a temperature range of -55°C to +150°C.

Feature Summary

• NPN epitaxial silicon planar design for signal amplification
• Low saturation voltage for efficient switching performance
• Halogen-free green molding compound compliant with IEC61249 standards

Applications

• General purpose amplifier circuits
• Switching applications in consumer electronics
• Signal processing in communication equipment

Procurement Notes

Verify the manufacturer designation on the component marking or datasheet header to confirm Taiwan Semiconductor Corporation origin, as this part number is widely produced by multiple vendors including Nexperia and Panjit. Ensure the specific suffix matches the required gain bin and packaging format. Cross-reference the RoHS compliance status and lead-free certification with the official product specification sheet provided by the supplier.

Selection Notes

Select this component when a low-voltage NPN transistor with moderate current handling is required for compact designs. The SOT-323 package offers space efficiency compared to larger through-hole alternatives. Consider the hFE binning requirements for your specific circuit gain needs, as variations exist between manufacturers. Verify thermal management capabilities given the 200 mW power dissipation limit in enclosed environments.

Part Context

This component belongs to the BC849 series of small-signal NPN transistors designed for general-purpose use. It serves as a standard replacement for legacy components in portable devices and industrial controls. The SOT-323 form factor is prevalent in modern surface-mount assembly lines, facilitating automated placement and high-volume manufacturing integration.

Replacement Considerations

Direct substitutes include BC849B variants from other manufacturers such as Nexperia or Diotec, provided the pinout and electrical ratings match. Verify that alternative sources offer the same SOT-323 package and hFE gain range to ensure circuit compatibility without redesign.