Infineon Technologies BF999E6433HTMA1

Overview

BF999E6433HTMA1 from Infineon Technologies is a silicon N-channel dual-gate MOSFET triode optimized for high-frequency amplification up to 300 MHz, specifically in FM receiver front-end and VHF/UHF RF amplifier stages; features 20 V V_DS, 30 mA I_D, 27 dB power gain at 45 MHz, 2.1 dB noise figure, and SOT23 package.

For engineers reviewing the BF999E6433HTMA1 datasheet, BF999E6433HTMA1 pinout, BF999E6433HTMA1 application, or BF999E6433HTMA1 equivalent, key selection criteria include RF gain-bandwidth trade-off, low-noise performance at VHF, gate isolation for mixer/amp cascading, and AEC-Q101 qualification for automotive infotainment RF modules.

Technical Context

This dual-gate MOSFET operates with independent control of G1 (signal input) and G2 (bias/control), enabling high reverse isolation (>30 dB typical) and stable gain tuning without affecting DC bias. Its transconductance peaks at 20 mS with 10 mA drain current, and C_gss = 2.5 pF / C_dss = 0.9 pF at 10 MHz support wideband matching.

The device is characterized at T_A = 25°C with V_DS = 10 V, I_D = 10 mA, and f = 45 MHz - conditions reflecting real-world FM tuner IF/RF amplifier operation. Thermal resistance R_th(ch–s) ≤ 370 K/W ensures reliable operation under continuous 200 mW dissipation at T_S ≤ 76°C.

Key Specifications

Pinout & Package

Package: SOT23 - surface-mount plastic package with 3-pin configuration, 1.3 mm pitch, and standard reel packaging (3,000 pcs/reel ø180 mm).

Key Features

Applications

Equivalent & Alternatives

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

Compared with BFG520/X and MRF901, BF999E6433HTMA1 uniquely balances automotive qualification, dual-gate isolation, and sub-2.5 dB noise in the 30–300 MHz band - making it the only option qualified for safety-critical RF front-ends in production vehicles.

Availability

BF999E6433HTMA1 is available at Aetrix Electronics and suitable for FM radio front-ends, automotive TPMS receivers, and VHF avionics receivers requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant manufacturing.

Supply support for BF999E6433HTMA1 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

Infineon Technologies AG is a German semiconductor manufacturer specializing in power management, automotive ICs, and RF components, with global R&D and wafer fabrication facilities.

The BF999 belongs to Infineon's legacy RF transistor product line, designed explicitly for high-isolation, low-noise amplification in analog FM/VHF receiver systems - not general-purpose switching or digital logic.

FAQ

What is the maximum operating frequency for stable small-signal gain?

BF999E6433HTMA1 maintains usable power gain up to 300 MHz, with measured G_p ≥ 15 dB at 200 MHz and ≥ 8 dB at 300 MHz under standard test conditions (V_DS = 10 V, I_D = 10 mA). Gain rolls off beyond this due to transconductance and capacitance limitations, not device failure.

Can G2 be left unconnected or tied directly to ground?

No - G2 must be DC-biased within −1.5 V to 0 V relative to source to maintain channel conduction and avoid cutoff. Floating G2 causes unpredictable threshold shift and gain collapse; grounding G2 without current-limiting resistor risks excessive gate current and device damage.

Is thermal derating required above 76°C board temperature?

Yes - total power dissipation must be linearly derated above T_S = 76°C at 2.7 mW/°C, per the P_tot vs. T_S curve. At T_S = 100°C, maximum allowed P_tot drops to 133 mW to maintain T_ch ≤ 150°C and ensure long-term reliability.

Does the SOT23 package support hand-soldering for prototyping?

Yes - the SOT23 footprint is compatible with fine-tip soldering irons and hot-air rework stations. Recommended profile: preheat 120°C for 60 s, ramp to 320°C peak in ≤30 s, dwell ≤5 s. Avoid mechanical stress on leads during cooling to prevent solder joint fracture.