2N4957

Bipolar RF Transistors Overview

The Microsemi 2N4957 is a silicon PNP bipolar junction transistor designed for general-purpose switching and amplification applications. It features a maximum collector-emitter voltage of 30 V and a continuous collector current rating of 30 mA. The device operates within an extended temperature range from -65°C to +200°C, supporting high-temperature environments. Key electrical characteristics include a DC current gain (hFE) ranging from 10 to 165 at a test condition of -5 mA and 10 V. The component has a maximum power dissipation of 200 mW and utilizes an LCC-3 surface-mount package.

Bipolar RF Transistors Feature Summary

• High-temperature operation capability up to 200°C junction temperature
• PNP polarity configuration for complementary circuit designs
• Surface-mount LCC-3 packaging for compact board integration

Bipolar RF Transistors Applications

• General-purpose switching circuits requiring high-temperature stability
• Amplifier stages in ruggedized electronic systems
• Complementary pairs with NPN transistors in linear applications

Bipolar RF Transistors Procurement Notes

Verify the manufacturer designation carefully, as Microchip Technology acquired Microsemi. Confirm the specific suffix indicates the LCC-3 surface-mount package rather than through-hole variants. Ensure the procurement source provides official datasheets confirming the 200°C operating limit and LCC-3 footprint compatibility before finalizing orders.

Bipolar RF Transistors Selection Notes

Select this component when a PNP transistor with a 30 V collector-emitter breakdown and 30 mA current capacity is required. The LCC-3 package suits space-constrained surface-mount designs. Verify that the application environment supports the specified -65°C to +200°C operating range and that the 200 mW power dissipation limit aligns with thermal management strategies.

Bipolar RF Transistors Part Context

The 2N4957 belongs to the standard military-grade and commercial bipolar transistor family historically associated with Microsemi. It serves as a PNP counterpart to NPN devices like the 2N4958. The part is characterized by its robust high-temperature performance and small outline LCC-3 package, distinguishing it from larger axial-leaded equivalents in the same numbering series.

Bipolar RF Transistors Replacement Considerations

Direct replacements must match the PNP type, 30V/30mA ratings, and LCC-3 package. Consider the 2N4958UB/TR for NPN equivalents or other Microchip LCC-3 PNP transistors with comparable hFE and thermal specifications. Verify pinout compatibility and thermal resistance values before substitution.