Infineon Technologies BF998E6327HTSA1

Overview

BF998E6327HTSA1 from Infineon Technologies is a silicon N-channel dual-gate MOSFET tetrode optimized for low-noise, gain-controlled RF amplification up to 800 MHz. It features two independent gates (G1, G2), 9 mA typical drain current (IDSS), 24 mS typical forward transconductance (gfs), and 1.8 dB noise figure at 800 MHz - deployed in VHF/UHF receiver front-ends for automotive keyless entry and remote keyless systems.

For engineers reviewing the BF998E6327HTSA1 datasheet, BF998E6327HTSA1 pinout, BF998E6327HTSA1 application, or BF998E6327HTSA1 equivalent, this device requires attention to gate biasing strategy, thermal derating above 76°C, gain control range (50 dB max), and SOT143 package layout constraints for RF impedance matching.

Technical Context

The BF998E6327HTSA1 implements a short-channel tetrode structure with isolated gate terminals enabling independent control of input impedance (via G1) and gain (via G2). Its high S/C quality factor and low feedback capacitance (25 fF) support stable broadband amplification without neutralization.

It operates with VG2S as the primary gain-control voltage (–2 V to +4 V), while VG1S sets pinch-off (–0.8 V to +2.5 V) and input matching. The device is characterized at VDS = 8 V, ID = 10 mA, and f = 10 MHz for capacitance, and at 45 MHz / 800 MHz for power gain and noise figure.

Key Specifications

Pinout & Package

SOT143 package: 4-pin surface-mount plastic package with gull-wing leads, 1.3 mm × 1.7 mm footprint, 0.95 mm height, and moisture sensitivity level (MSL) 1. Pin 1 = Source (S), Pin 2 = Drain (D), Pin 3 = Gate 2 (G2), Pin 4 = Gate 1 (G1).

Key Features

Applications

Equivalent & Alternatives

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

Compared with BFP181E6327HTSA1 and NE85633, BF998E6327HTSA1 offers optimal balance of noise (1.8 dB), gain control range (50 dB), and thermal performance (Rthchs ≤370 K/W) for new UHF receiver designs requiring wide dynamic range and automotive qualification.

Availability

BF998E6327HTSA1 is available at Aetrix Electronics and suitable for automotive keyless entry systems, TPMS receivers, ISM band remote controls, and UHF RFID readers requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for BF998E6327HTSA1 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 is a German semiconductor manufacturer specializing in power management, automotive electronics, and RF solutions, with global manufacturing and R&D centers.

The BF998 belongs to Infineon's RF Transistor product line, designed specifically for high-performance, low-noise amplification in automotive and industrial wireless communication systems up to 1 GHz.

FAQ

What is the recommended gate biasing configuration for optimal noise figure?

For minimum noise figure at 800 MHz, bias VG1S at –0.4 V and VG2S at +4 V with VDS = 8 V and ID ≈ 10 mA. This configuration achieves 1.8 dB NF while maintaining 24 mS gfs. Use decoupled 100 kΩ potentiometers for fine-tuning, and ensure G1 and G2 bias lines include 100 Ω gate stopper resistors and 100 nF bypass capacitors to ground.

Can BF998E6327HTSA1 be used in push-pull or Class AB RF amplifier topologies?

No - the BF998E6327HTSA1 is a single-ended, enhancement-mode N-channel tetrode intended for Class A small-signal amplification only. Its dual-gate architecture does not support complementary symmetry or push-pull drive. Attempting Class AB operation risks thermal runaway due to lack of inherent current mirroring or matched pair characteristics.

How does the SOT143 package affect RF layout and grounding?

The SOT143 package requires direct source (Pin 1) connection to a solid RF ground plane with ≥4 thermal vias (0.3 mm diameter) within 2 mm of the pad. Keep G1 and G2 traces <2 mm long and 0.15 mm wide; place DC blocking capacitors (100 pF NP0) within 0.5 mm of respective gate pins to suppress parasitic resonance above 1 GHz.

Is BF998E6327HTSA1 suitable for 2.4 GHz ISM band applications?

No - its gain and noise performance degrade significantly above 1 GHz. At 2.4 GHz, measured power gain drops below 3 dB and noise figure exceeds 5 dB, making it unsuitable for Bluetooth or Wi-Fi front-ends. For 2.4 GHz, consider Infineon's BGA28xx series GaAs pHEMTs or BFP640 transistor family instead.