NXP Semiconductors BF1203,115

Overview

BF1203,115 from NXP Semiconductors is a dual N-channel dual-gate MOSFET designed for low-noise, gain-controlled RF amplification in VHF/UHF tuners and professional communications equipment. It integrates two independent amplifiers sharing source and gate 2 terminals, with typical forward transfer admittance of 28 mS (amp a) and 30 mS (amp b), input capacitance of 2.6 pF and 1.7 pF respectively, and noise figure as low as 1.0 dB at 400 MHz.

For engineers reviewing the BF1203,115 datasheet, BF1203,115 pinout, BF1203,115 application, or BF1203,115 equivalent, this device supports AGC-stable operation in 3–9 V supply systems, delivers superior cross-modulation performance (≥105 dBµV at 40 dB AGC), and enables compact dual-amplifier front-end designs in SOT363 micro-miniature packaging.

Technical Context

The BF1203,115 implements two discrete dual-gate MOSFET amplifier cells in one monolithic die, with shared source and gate 2 leads enabling synchronized AGC control. Internal bias circuits provide DC stabilization and minimize intermodulation distortion during gain adjustment.

Integrated protection diodes between each gate and source suppress input voltage surges, while the SOT363 package ensures thermal resistance of 240 K/W from junction to soldering point and supports operation up to 150 °C junction temperature.

Key Specifications

Pinout & Package

The BF1203,115 is housed in a SOT363 (SC-88) 6-pin micro-miniature plastic surface-mount package measuring 2.2 × 1.35 × 1.15 mm with 0.65 mm pitch. Pin 1 index is marked by a notch or dot on the package top surface.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-gate MOSFET amplifier applications.

Compared with BF1203,115, BF1204,115 offers higher gain for extended UHF coverage, while BF1205,115 delivers lower noise for critical SNR-limited systems-both retain full pin compatibility and require no PCB changes.

Availability

BF1203,115 is available at Aetrix Electronics and suitable for analog/digital TV tuners, professional communications receivers, and RF test equipment requiring stable component supply with consistent parametric performance across production lots.

Supply support for BF1203,115 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 consumer, industrial, and communications markets.

The BF1203,115 belongs to NXP's legacy RF transistor product line, engineered specifically for gain-stable, low-noise amplification in broadcast and professional VHF/UHF receiver front-ends.

FAQ

What is the maximum drain-source voltage rating for the BF1203,115?

The BF1203,115 has a maximum drain-source voltage (V_DS) rating of 10 V, as defined in the Absolute Maximum Ratings table. This limit applies per MOSFET cell and must not be exceeded under any operating condition-including transient spikes-to prevent permanent device damage. The BF1203,115 is intended for use in 3–9 V supply systems, making this rating sufficient for standard tuner and receiver applications.

How does the shared gate 2 configuration affect AGC implementation in the BF1203,115?

The BF1203,115 uses a shared gate 2 terminal for both amplifier cells, allowing a single AGC control voltage to simultaneously adjust gain across both paths. This eliminates need for matched control circuitry and ensures correlated gain reduction-critical for maintaining channel balance in dual-tuner or diversity-reception architectures. The BF1203,115 achieves ≥105 dBµV cross-modulation rejection at 40 dB AGC due to this architecture.

Can the BF1203,115 operate reliably at 800 MHz, and what is its noise performance there?

Yes, the BF1203,115 is characterized for operation up to 1000 MHz. At 800 MHz, amplifier b delivers a typical noise figure of 1.1 dB with 30 mS forward transfer admittance at I_D = 12 mA. This makes the BF1203,115 suitable for UHF digital terrestrial TV and professional communications systems where low added noise and stable gain are essential at high frequencies.

What is the thermal resistance from junction to soldering point for the BF1203,115, and why does it matter?

The BF1203,115 has a thermal resistance (R_{th j-s}) of 240 K/W from junction to soldering point, measured at the source lead. This value directly impacts safe operating area under continuous DC bias: at 30 mA drain current and 5 V V_DS, power dissipation reaches ~150 mW, requiring careful PCB copper pour design to maintain T_j ≤ 150 °C. The BF1203,115's SOT363 package relies on source-pad thermal conduction for reliability in sealed tuner modules.

Are external gate protection diodes required when using the BF1203,115?

No, external gate protection diodes are not required for the BF1203,115. The device integrates internal diodes between each gate (gate 1 a/b and gate 2) and the shared source terminal to protect against electrostatic discharge and input voltage surges. This feature is explicitly documented in the "DESCRIPTION" section of the datasheet and confirmed by the caution note regarding anti-static packaging. The BF1203,115 thus simplifies front-end design while maintaining robustness in handling environments.