Infineon Technologies BFP840FESDH6327XTSA1

Overview

BFP840FESDH6327XTSA1 from Infineon is a discrete SiGe:C NPN RF heterojunction bipolar transistor (HBT) with integrated ESD protection, designed for 5 GHz band front-end amplification in WLAN and satellite navigation receivers. It delivers NFmin = 0.75 dB at 5.5 GHz, fT = 85 GHz, Gms = 23 dB, OIP3 = 22 dBm, and supports VCC as low as 1.2 V.

For engineers reviewing the BFP840FESDH6327XTSA1 datasheet, BFP840FESDH6327XTSA1 pinout, BFP840FESDH6327XTSA1 application, or BFP840FESDH6327XTSA1 equivalent, key selection criteria include minimum noise figure at 5.5 GHz, ESD hardness (1.5 kV HBM), TSFP-4-1 package compatibility, and DC bias flexibility across 1.2–3.6 V supply rails.

Technical Context

This HBT leverages SiGe:C technology to achieve high fT (85 GHz) and ultra-low noise performance at microwave frequencies, enabling high-sensitivity LNA designs in compact 5 GHz systems. Its dual-emitter configuration (Pins 1 & 4 = E) supports balanced input matching and thermal symmetry.

The device operates under fixed-VCE bias (1.8 V typical), with verified AC performance up to 5.5 GHz including transducer gain ≥19 dB, NFmin ≤0.75 dB, and OIP3 ≥22 dBm at IC = 10 mA - all measured in 50 Ω test fixtures with Bias-T networks.

Key Specifications

Pinout & Package

Package: TSFP-4-1 - ultra-compact surface-mount plastic package (1.1 × 0.7 × 0.4 mm), optimized for high-frequency layout with short internal lead lengths and symmetric emitter terminals.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BFP740FESD and NE85633, the BFP840FESDH6327XTSA1 offers superior noise performance (0.75 dB vs. ≥0.8 dB), higher OIP3 (22 dBm vs. ≤20 dBm), and built-in 1.5 kV HBM protection - making it the preferred choice for miniaturized, high-reliability 5 GHz receiver front-ends where component count and layout area are constrained.

Availability

BFP840FESDH6327XTSA1 is available at Aetrix Electronics and suitable for WLAN 5 GHz LNA modules, GNSS navigation receivers, and WiMAX base station front-ends requiring stable component supply, consistent parametric performance, and JEDEC-qualified reliability.

Supply support for BFP840FESDH6327XTSA1 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, RF, and automotive ICs, with leadership in SiGe:C transistor technology for high-frequency applications.

The BFP840FESD belongs to Infineon's high-performance RF transistor product line, engineered specifically for low-noise, high-linearity amplification in 1–6 GHz wireless infrastructure and precision navigation systems.

FAQ

What is the maximum allowable collector voltage for continuous operation?

The absolute maximum VCEO is 2.25 V at TA = 25 °C with open base. Operation above this requires a series collector resistor to limit voltage drop across the transistor. At −55 °C, the derated limit is 2.0 V. Exceeding these values risks irreversible junction damage.

Can BFP840FESDH6327XTSA1 operate from a 1.2 V supply?

Yes - the device is characterized and functional at VCC = 1.2 V, delivering usable gain and noise performance. Data sheet Table 6–12 confirm stable AC characteristics (Gms, NFmin, OIP3) at 1.8 V, but application notes verify 1.2 V operation with minor NF degradation (<0.1 dB) and reduced OIP3 (~19 dBm).

How is the dual-emitter configuration (Pins 1 & 4) implemented in PCB layout?

Both emitter pins must be connected together externally using a low-inductance trace or copper pour. This reduces total emitter series inductance, improves thermal spreading, and enhances high-frequency stability. A shared 0402 bypass capacitor to ground near both pins is recommended.

Is the TSFP-4-1 package compatible with standard reflow profiles?

Yes - the TSFP-4-1 package is qualified for lead-free reflow per J-STD-020, with peak temperature up to 260 °C. Thermal resistance RthJS = 541 K/W requires attention to solder pad thermal relief; full copper pour under the package is advised to maintain TJ ≤150 °C at Ptot = 75 mW.