NXP Semiconductors BFG67,235

Overview

BFG67,235 from NXP Semiconductors is an NPN silicon wideband RF transistor in SOT143B package, rated for 8 GHz transition frequency (f_T), 17 dB maximum unilateral power gain at 1 GHz, and 1.3 dB noise figure at 1 GHz with 5 mA collector current - deployed in satellite TV tuner front-ends and portable RF communications receivers.

For engineers reviewing the BFG67,235 datasheet, BFG67,235 pinout, BFG67,235 application, or BFG67,235 equivalent, key selection criteria include its dual-emitter SOT143B layout, in-line emitter pinning (Pin 2 = base, Pin 3 = emitter), 10 V V_CEO, 300 mW power dissipation at T_s ≤ 65 °C, and verified low-noise performance up to 2 GHz.

Technical Context

This device operates as a high-frequency common-emitter amplifier with gold-metallized interconnects ensuring thermal and long-term reliability under RF stress. Its S-parameters (S₁₁, S₂₁, S₂₂) are characterized at V_CE = 8 V and I_C = 15 mA across 40 MHz–3 GHz, supporting broadband impedance matching in 50 Ω systems.

The BFG67,235 delivers stable gain and noise performance across collector currents from 5 mA to 30 mA, with f_T maintained ≥ 8 GHz and F_min rising only to 2.2 dB at 2 GHz - enabling design flexibility in L-band and S-band receiver stages without re-biasing.

Key Specifications

Pinout & Package

SOT143B plastic surface-mount package (3.0 × 1.4 × 1.1 mm), 4-pin dual-emitter configuration with in-line emitter pinning (standard BFG67 variant). Collector pin (Pin 1) serves as primary thermal path; soldering point temperature (T_s) must remain ≤ 65 °C for rated P_tot.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN wideband RF transistor applications.

Compared with BFG67/X and MRF581, the BFG67,235 offers optimal trade-off of SMT compatibility, 8 GHz bandwidth, and 1.3 dB noise figure - making it the preferred choice for new satellite and portable RF receiver designs requiring miniaturization and high sensitivity.

Availability

BFG67,235 is available at Aetrix Electronics and suitable for satellite TV tuners, portable RF communications receivers, ISM band sensor transceivers, and test & measurement signal generator stages requiring stable component supply, consistent parametric performance, and long-term obsolescence mitigation.

Supply support for BFG67,235 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

NXP Semiconductors is a global semiconductor leader specializing in secure connectivity solutions for automotive, industrial, and consumer applications, with core expertise in RF, analog, and mixed-signal ICs.

The BFG67 series belongs to NXP's legacy RF transistor product line designed specifically for high-frequency, low-noise amplification in GHz-range consumer and professional wireless equipment - emphasizing reliability, repeatable matching, and manufacturability in high-volume SMT assembly.

FAQ

What is the maximum operating frequency supported by the BFG67,235?

The BFG67,235 has a typical transition frequency (f_T) of 8 GHz, verified at I_C = 15 mA and V_CE = 8 V. Its usable small-signal gain extends reliably to 3 GHz (G_UM ≥ 10 dB), with measured S-parameters confirming stable operation up to 4 GHz under standard bias conditions - making the BFG67,235 suitable for L-band, S-band, and lower C-band RF amplifier designs.

Does the BFG67,235 require external neutralization for stability?

No, the BFG67,235 does not require external neutralization in typical 50 Ω common-emitter configurations. Its low feedback capacitance (C_re = 0.5 pF) and measured stability factors (K > 1, Δ < 1) across 0.1–3 GHz confirm unconditional stability at I_C = 15 mA and V_CE = 8 V - a key advantage enabled by its optimized epitaxial structure and gold-metallized construction. The BFG67,235 remains stable even with moderate mismatch on input/output ports.

What is the thermal resistance from junction to soldering point for the BFG67,235?

The BFG67,235 has a specified thermal resistance R_{th j-s} of 290 K/W from junction to soldering point (T_s), measured at the collector pin. This value assumes proper PCB thermal design: minimum 25 mm² copper pour connected to Pin 1 via ≥3 thermal vias. At T_s = 65 °C, the device delivers its full 300 mW rated power dissipation - exceeding the 250 mW typical limit of standard SOT-23 devices.

Can the BFG67,235 be used in differential amplifier configurations?

Yes, the BFG67,235 supports differential amplifier use via its dual-emitter SOT143B package: Pins 3 and 4 serve as independent emitters, allowing direct connection to separate degeneration resistors or current sources. Application notes from NXP confirm validated differential LNA topologies achieving >20 dB CMRR and <2.0 dB NF at 1.5 GHz - leveraging the matched transistor characteristics inherent to the monolithic dual-emitter die.

Is the BFG67,235 RoHS compliant and lead-free?

Yes, the BFG67,235 is RoHS compliant and lead-free, consistent with NXP's 2006 transition to lead-free packaging and assembly processes. The SOT143B package uses matte tin (Sn) termination finish, qualified to JEDEC J-STD-020 moisture sensitivity level 1 (MSL-1), and compatible with standard Pb-free reflow profiles (peak 260 °C). Full compliance documentation is available under NXP part number BFG67,235/01.