NXP Semiconductors BFQ67W,135

Overview

BFQ67W from NXP Semiconductors is an NPN wideband RF transistor in SOT323 package, rated for 8 GHz transition frequency (f_T), 13 dB maximum unilateral power gain (G_UM) at 1 GHz, and 1.3 dB noise figure at 1 GHz with I_C = 5 mA. It serves as a low-noise amplifier stage in satellite TV tuners and portable RF communications equipment up to 2 GHz.

For engineers reviewing the BFQ67W datasheet, BFQ67W pinout, BFQ67W application, or BFQ67W equivalent, key selection criteria include its f_T = 8 GHz, G_UM = 13 dB @ 1 GHz, F = 1.3 dB @ 1 GHz, V_CEO = 10 V, and SOT323 thermal resistance R_{th j-s} = 190 K/W - all critical for RF front-end gain block and LNA design.

Technical Context

The BFQ67W employs gold metallization for enhanced reliability under RF stress and operates with a common-emitter configuration optimized for broadband small-signal amplification. Its S-parameter behavior (S₁₁, S₂₁, S₁₂, S₂₂) is characterized up to 3 GHz, supporting impedance matching across 40 MHz–2 GHz bands.

Designed for fixed-bias or stabilized bias networks, it delivers stable gain (G_UM ≥ 8 dB) and low noise (F ≤ 2.7 dB) at I_C = 15 mA, V_CE = 8 V, with collector capacitance C_c = 0.7 pF and feedback capacitance C_re = 0.5 pF enabling high-frequency stability without neutralization.

Key Specifications

Pinout & Package

BFQ67W uses the plastic SOT323 (SC-70) surface-mount package with 3 leads and gold metallization for corrosion resistance and wire-bond reliability. The package features a collector tab for thermal conduction and is compatible with standard reflow profiles.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BFR92A,115 and MRF581, the BFQ67W offers superior f_T and SOT323 footprint efficiency for space-constrained 1–2 GHz LNA designs, though its 3-pin configuration requires careful ground routing to avoid emitter inductance penalties.

Availability

BFQ67W is available at Aetrix Electronics and suitable for satellite TV tuners, portable RF transceivers, UHF wireless microphones, and CATV distribution amplifiers requiring stable component supply across industrial and broadcast production programs.

Supply support for BFQ67W 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 company specializing in high-performance RF, analog, and mixed-signal solutions for automotive, industrial, and consumer markets.

The BFQ67W belongs to NXP's legacy RF transistor product line, engineered specifically for broadband low-noise amplification in consumer satellite and wireless communication equipment operating below 2 GHz.

FAQ

What is the maximum operating frequency supported by the BFQ67W?

The BFQ67W has a transition frequency (f_T) of 8 GHz, but its usable small-signal gain is validated up to 2 GHz per datasheet Figures 7–9 and application description. At 2 GHz, G_UM remains ≥8 dB with I_C = 15 mA and V_CE = 8 V, making BFQ67W suitable for LNA and driver stages in sub-2 GHz RF systems.

Does the BFQ67W require neutralization for stability?

The BFQ67W exhibits low feedback capacitance (C_re = 0.5 pF), and datasheet S-parameter plots (Fig.14) confirm |S₁₂| < 0.1 up to 2 GHz. This enables unconditional stability in common-emitter configurations without neutralization, provided proper input/output impedance matching and grounding are implemented for BFQ67W.

What is the recommended bias condition for minimum noise figure in BFQ67W?

For minimum noise figure (F_min = 1.5 dB), the BFQ67W should be biased at I_C = 5 mA, V_CE = 8 V, with source impedance tuned to Γ_opt as shown in Fig.11. This condition yields F = 1.3 dB at 1 GHz and is explicitly validated in the "Noise figure" characteristics table for BFQ67W.

Can BFQ67W be used in Class A power amplifier applications?

The BFQ67W is characterized for small-signal operation only, with P_tot = 300 mW and I_C max = 50 mA. Its G_UM and harmonic distortion data are not specified for large-signal conditions. Therefore, BFQ67W is not recommended for Class A power amplification; it is optimized as a low-noise voltage/current gain device, not a power switch or PA transistor.

Is the BFQ67W pin-compatible with other SOT323 NPN transistors like the MMBT2222?

No - the BFQ67W pinout (1=Base, 2=Emitter, 3=Collector) differs from MMBT2222 (1=Emitter, 2=Base, 3=Collector). Substituting BFQ67W into an MMBT2222 layout would reverse bias polarity and cause immediate failure. Always verify pin mapping using the "PINNING" section of the BFQ67W datasheet before board reuse.