2N2857UB

Bipolar RF Transistors Overview

The Microsemi Corporation 2N2857UB is a silicon NPN RF small signal bipolar transistor designed for ultra-high frequency applications. It features a maximum collector-emitter voltage of 15 V and an emitter-base voltage of 3 V. The device supports a continuous collector current of 40 mA with a minimum DC current gain (hFE) of 30. It operates within a temperature range of -65 °C to +200 °C and has a power dissipation rating of 200 mW. The component utilizes a UB-3 package configuration suitable for surface mount or specific hermetic sealing requirements.

Bipolar RF Transistors Feature Summary

• Hermetically sealed ceramic construction ensuring reliability in harsh environments
• Ultra-high frequency band operation capability for RF applications
• Qualified under MIL-PRF-19500 standards for military-grade performance

Bipolar RF Transistors Applications

• Military radio frequency amplification circuits
• High-reliability aerospace communication systems
• Defense electronics requiring radiation testing compliance

Bipolar RF Transistors Procurement Notes

Verify the specific qualification level suffix, as the base part number corresponds to multiple grades including JAN, JANTX, JANTXV, and JANS. Confirm that the supplier provides documentation for MIL-STD-750 visual inspection and radiation testing results if required for the intended mission profile. Ensure the package type matches the design constraints.

Bipolar RF Transistors Selection Notes

Select this component when high thermal stability up to 200 °C is required alongside low voltage operation. The 40 mA current limit and 15 V breakdown voltage define the operational boundaries for small-signal RF stages. Consider the UB-3 package dimensions for board layout compatibility and verify the necessary screening level against the system's environmental stress specifications.

Bipolar RF Transistors Part Context

This transistor belongs to the 2N2857 family offered by Semicoa and Microsemi, covering various military qualification levels. The series includes variants such as 2N2857UBJ, 2N2857UBJX, 2N2857UBJV, and 2N2857UBJS. Each variant adheres to specific MIL-PRF-19500 appendices, providing options for different reliability and screening requirements while maintaining identical electrical characteristics.

Bipolar RF Transistors Replacement Considerations

Direct substitutes include other 2N2857UB variants with different qualification suffixes (e.g., J, JX, JV, JS). Verify that any replacement maintains the same UB-3 package and hermetic sealing properties to ensure mechanical and environmental compatibility.