KSP43BU

Single Bipolar Transistors Overview

The KSP43BU is an NPN silicon epitaxial planar transistor manufactured by Fairchild Semiconductor, now part of onsemi. It features a TO-92-3 through-hole package and supports a maximum collector-emitter voltage (VCEO) of 200 V and a collector-base voltage (VCBO) of 200 V. The device handles a continuous collector current of 500 mA with a power dissipation rating of 625 mW. Key electrical parameters include a minimum DC current gain (hFE) of 40, a collector-emitter saturation voltage of 500 mV, and a transition frequency (fT) of 50 MHz. It operates within a temperature range up to +150°C.

Single Bipolar Transistors Feature Summary

• High voltage capability with 200 V collector-emitter breakdown
• Suitable for general-purpose switching and amplification applications
• Robust thermal performance with a maximum junction temperature of +150°C

Single Bipolar Transistors Applications

• General-purpose high-voltage switching circuits
• Amplifier stages requiring moderate current handling
• Industrial control systems utilizing through-hole mounting

Single Bipolar Transistors Procurement Notes

Verify the manufacturer status carefully, as the component is listed as obsolete or end-of-life. Confirm if the specific batch originates from Fairchild Semiconductor legacy stock or onsemi production, as branding may vary. Ensure the TO-92-3 package matches your PCB footprint requirements. Check RoHS compliance documentation for the specific manufacturing date code before procurement.

Single Bipolar Transistors Selection Notes

Select this component when a 200 V NPN transistor is required in a low-power through-hole package. It serves as a direct replacement for other KSP43 variants with identical electrical ratings but different suffixes. Consider the 500 mA current limit and 625 mW power dissipation constraints during circuit design. Verify that the 50 MHz bandwidth meets the signal frequency requirements of the application.

Single Bipolar Transistors Part Context

The KSP43BU belongs to the KSP43 series of high-voltage transistors originally developed by Fairchild Semiconductor. This series includes complementary PNP devices like the KSP92BU. The component represents legacy silicon technology designed for reliable operation in industrial and consumer electronics. Its discontinuation reflects the industry shift toward surface-mount technologies and newer fabrication processes.

Single Bipolar Transistors Replacement Considerations

• KSP42BU (300V variant)
• MMBT6520L (Modern equivalent)