BUL128

Single Bipolar Transistors Overview

The BUL128 is a high voltage fast-switching NPN power transistor manufactured using Multi Epitaxial Planar technology. It features a Cellular Emitter structure with planar edge termination to enhance switching speeds while maintaining a wide Reverse Biased Safe Operating Area (RBSOA). The device is housed in a TO-220 package and is designed for lighting applications and low-cost switch-mode power supplies.

Single Bipolar Transistors Feature Summary

• High voltage capability with medium voltage operation
• Very high switching speed utilizing Cellular Emitter structure
• Wide Reverse Biased Safe Operating Area (RBSOA)
• Low spread of dynamic parameters for reliable operation

Single Bipolar Transistors Applications

• Electronic ballasts for fluorescent lighting
• Flyback and forward single transistor low power converters
• Low cost switch-mode power supplies

Single Bipolar Transistors Procurement Notes

Verify the specific ordering suffix against official STMicroelectronics documentation, as suffixes may indicate variations in packaging or tape-and-reel configurations. Confirm that the component meets RoHS compliance requirements if applicable to your design constraints. Ensure thermal management solutions align with the specified junction-to-case and junction-to-ambient thermal resistance values provided in the datasheet.

Single Bipolar Transistors Selection Notes

Select this component when high voltage handling and rapid switching are required in compact designs. The TO-220 package facilitates efficient heat dissipation through the mounting base. Consider the pre-selected DC current gain groups (A and B) for consistent performance in amplification or switching circuits requiring predictable hFE characteristics across production batches.

Single Bipolar Transistors Part Context

This NPN power transistor belongs to STMicroelectronics' legacy discrete semiconductor portfolio. It utilizes advanced epitaxial processes optimized for high-voltage applications. The device serves as a robust solution for industrial and consumer electronics requiring reliable power switching under demanding electrical conditions.

Single Bipolar Transistors Replacement Considerations

Consult official cross-reference lists for verified substitutes. Ensure replacement parts match the TO-220 footprint, pinout configuration, and maximum voltage/current ratings to maintain circuit integrity without redesign.

Single Bipolar Transistors FAQ

What technology is used to manufacture the BUL128?

The BUL128 is manufactured using high voltage Multi Epitaxial Planar technology.

How does the BUL128 achieve high switching speeds?

It uses a Cellular Emitter structure with planar edge termination to enhance switching speeds while maintaining a wide RBSOA.

Is the DC current gain standardized for this part?

Yes, the product is pre-selected in DC current gain into Group A and Group B for reliable operation.