MMBTH81

Overview

The MMBTH81 is a small-signal bipolar junction transistor manufactured by onsemi, housed in an SOT-23 surface-mount package. It functions as a high-speed switching device designed for low-voltage digital applications. The component features a maximum collector-emitter voltage of 50V and a continuous collector current rating of 100mA. Key electrical characteristics include a DC current gain (hFE) range typically between 100 and 300 at specified test conditions. The device operates with a transition frequency sufficient for general-purpose switching tasks, ensuring reliable performance in compact electronic circuits requiring efficient signal control.

Feature Summary

• Compact SOT-23 surface-mount packaging for automated assembly
• High-speed switching capability for digital logic interfaces
• Low saturation voltage for improved power efficiency
• Robust thermal stability within standard operating temperature ranges

Applications

• General-purpose switching in consumer electronics
• Driver circuits for LEDs and relays
• Logic level translation in microcontroller systems
• Signal switching in portable devices

Procurement Notes

Verify the exact ordering suffix to confirm specific binning or tape-and-reel specifications. Ensure compatibility with existing PCB footprints and reflow soldering profiles. Cross-reference datasheet revisions to confirm parameter consistency before finalizing procurement orders for production runs.

Selection Notes

Select this component when a small-form-factor NPN transistor is required for low-current switching applications. Evaluate the hFE binning requirements against circuit gain needs. Confirm that the SOT-23 package dimensions fit the available board space and thermal management constraints of the design.

Part Context

This part belongs to onsemi's portfolio of small-signal transistors optimized for modern surface-mount technology. It serves as a direct replacement for legacy through-hole equivalents in miniaturized designs. The MMBTH81 supports the industry trend toward higher component density and reduced assembly costs in mass-produced electronic goods.

Replacement Considerations

Check pinout compatibility with existing designs. Verify that substitute parts meet or exceed the 50V VCEO and 100mA IC ratings. Ensure thermal resistance values are comparable to maintain reliability under similar load conditions.