BFG520,235

Overview

The BFG520,235 is an NPN silicon planar epitaxial transistor manufactured by NXP Semiconductors. It is designed for RF frontend applications in the GHz range and is encapsulated in a 4-pin plastic SOT143B envelope. Key electrical specifications include a collector-base voltage of 20 V, a collector-emitter voltage of 15 V, and a maximum DC collector current of 70 mA. The device features a transition frequency of 9 GHz at 20 mA and 6 V, with a total power dissipation of 300 mW up to a soldering point temperature of 88 °C. At 900 MHz, it provides a typical insertion power gain of 18 dB and a minimum noise figure of 1.1 dB when biased at 5 mA.

Feature Summary

• High power gain suitable for broadband amplification
• Low noise figure optimized for sensitive receiver frontends
• High transition frequency enabling operation in the GHz range
• Gold metallization ensuring excellent reliability

Applications

• Analog and digital cellular telephones
• Cordless telephones (CT1, CT2, DECT)
• Radar detectors
• Satellite TV tuners (SATV)
• Repeater amplifiers in fibre-optic systems

Procurement Notes

Verify the specific ordering suffix against the manufacturer's latest documentation to confirm pin configuration compatibility. The BFG520/X variant utilizes reverse pinning compared to the standard BFG520. Ensure the selected package matches the required PCB footprint and thermal management strategy for the target application environment.

Selection Notes

Select this component for low-noise amplifier stages requiring high gain at frequencies up to 2 GHz. Consider the bias current requirements, as noise performance varies significantly between 5 mA and 20 mA operating points. Evaluate the thermal resistance characteristics if operating near the maximum power dissipation limits or in enclosed spaces.

Part Context

This device belongs to the BFG520 family of NPN wideband transistors produced by NXP Semiconductors. It serves as a specialized RF component distinct from general-purpose logic or power switching devices. The product line includes variants such as BFG520/X and BFG520/XR, which share similar electrical characteristics but differ in physical pinout arrangements.

Replacement Considerations

Direct substitutes within the same family include BFG520/X and BFG520/XR. Note that these variants feature different pin configurations; verify schematic compatibility before substitution. No other cross-manufacturer equivalents are confirmed in the provided documentation.