CMKT3946 TR PBFREE

Overview

The CMKT3946 is a surface-mount silicon dual complementary small-signal switching transistor housed in an SOT-363 package. It integrates one NPN and one PNP transistor, marked as K46. Maximum ratings at 25°C include collector-base voltages of 60V (NPN) and 40V (PNP), continuous collector current of 200mA, and power dissipation of 350mW. The junction temperature range spans -65 to +150°C. Electrical characteristics specify saturation voltages up to 0.40V at 50mA base drive, DC current gains ranging from 30 to 300 depending on collector current, and transition frequencies of 300MHz for NPN and 250MHz for PNP.

Feature Summary

• Integrates complementary NPN and PNP transistors in a single space-saving SOT-363 package
• Designed for general-purpose amplifier and switching applications
• Features low saturation voltage and high current gain for efficient signal processing

Applications

• Small signal general purpose amplification
• Digital switching circuits
• Complementary push-pull output stages

Procurement Notes

Verify the component marking code K46 and SOT-363 package type upon receipt. Confirm the PBFREE suffix indicates lead-free plating compliance with manufacturer standards. Cross-reference datasheet electrical limits against specific circuit requirements to ensure operation within safe thermal and voltage boundaries during assembly and testing.

Selection Notes

Select this component when space constraints require a dual complementary pair in a compact surface-mount form factor. Ensure the design operates within the specified 200mA continuous collector current limit and 350mW power dissipation threshold. Verify that the required switching speeds and current gains align with the documented hFE and fT parameters for the target application frequency.

Part Context

This device belongs to Central Semiconductor's line of complementary small-signal transistors, functionally equivalent to the widely used 2N3904/2N3906 pair but consolidated into a single six-lead SOT-363 package. The integration reduces board footprint while maintaining standard switching performance characteristics suitable for portable electronics and compact industrial control modules.

Replacement Considerations

Direct functional substitutes include other SOT-363 complementary pairs such as the BC847BC or MMBT3904/MMBT3906 combinations. Verify pinout compatibility, specifically emitter and collector assignments, as lead configurations may vary between manufacturers despite identical package styles.