2N5308

Overview

The onsemi 2N5308 is an NPN silicon Darlington transistor housed in a TO-92 package. It features a maximum collector current of 1.2 A and a collector-emitter voltage rating of 40 V. The device provides high DC current gain, with minimum values of 7,000 at 2 mA and 20,000 at 100 mA. Total power dissipation is rated at 625 mW, with a junction-to-ambient thermal resistance of 200 °C/W. Operating temperatures range from -55°C to +150°C.

Feature Summary

• Designed for applications requiring extremely high current gain at currents up to 1.0 A
• Utilizes a standard TO-92 through-hole cylindrical plastic/epoxy package
• Constructed using silicon semiconductor material

Applications

• High-gain switching circuits
• Driver stages for power transistors
• Low-side switching in portable equipment

Procurement Notes

Verify the manufacturer source carefully, as this component was originally produced by Fairchild Semiconductor. Confirm that the specific unit received matches the electrical characteristics and pinout defined in the official datasheet. Ensure the package type is correctly identified as TO-92 before integration into the design.

Selection Notes

Select this component when a single NPN device offers sufficient current handling and voltage ratings for low-power switching tasks. The high current gain reduces base drive requirements compared to standard bipolar transistors. Consider the thermal resistance limits if operating near maximum current levels or in enclosed environments.

Part Context

This part belongs to the family of small-signal NPN Darlington transistors. It serves as a discrete alternative to integrated driver ICs for moderate load applications. The TO-92 form factor allows for easy prototyping and manual assembly on breadboards or perf boards.

Replacement Considerations

The MPSA14 is documented as having similar characteristics. Verify pin compatibility and exact gain specifications before substituting.