Infineon Technologies BGB 540 E6327

Overview

BGB540 from Infineon Technologies is an active biased NPN RF transistor in SOT343 package, designed as a monolithic microwave integrated circuit (MMIC) for high-gain, low-noise amplification at 1.8 GHz. It delivers 18 dB maximum stable power gain, 1.15 dB noise figure at 0.9 GHz, and 12 dBm P-1dB output power under 2 V bias and 20 mA collector current-key for front-end LNA stages in cellular handsets.

For engineers reviewing the BGB540 datasheet, BGB540 pinout, BGB540 application, or BGB540 equivalent, this device requires attention to its open-collector output configuration, externally adjustable bias current via RBias, SIEGET®-45 process characteristics, and thermal derating above 75°C ambient.

Technical Context

The BGB540 integrates on-chip biasing circuitry enabling IC = 10 × IBias control, eliminating external base bias resistors in many configurations. Its SIEGET®-45 silicon epitaxial technology ensures high fT (~25 GHz), low CCB (0.15 pF at 2 V), and stable gain across 0.1–6 GHz.

It operates with supply voltage from 1.4 V to 4.3 V and supports DC-coupled RF input/output. The open-collector output allows flexible impedance matching and cascode staging, while the 4-pin SOT343 layout separates RF In (Emitter), RF Out (Collector), Bias (Base), and Ground (Case).

Key Specifications

Pinout & Package

SOT343 (4-pin plastic surface-mount package) with exposed emitter pad for thermal conduction and RF grounding. Pin 1 = Base (Bias), Pin 2 = Emitter (RF In), Pin 3 = Collector (RF Out), Pin 4 = Case/Ground (connected internally to emitter lead).

Key Features

Applications

Equivalent & Alternatives

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

Compared with BFP405H6327 and MMA040407-100, the BGB540 uniquely balances tunable gain, low NF, and minimal external components-making it optimal for cost-sensitive, performance-targeted cellular front ends where IBias adjustment replaces full bias network redesign.

Availability

BGB540 is available at Aetrix Electronics and suitable for cellular handset LNA design, SAT-TV LNB modules, cordless phone RF front ends, and high-frequency oscillator buffering requiring stable component supply and long-lifecycle support.

Supply support for BGB540 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, RF, automotive, and security ICs, with global R&D and manufacturing infrastructure.

The BGB540 belongs to Infineon's Wireless Silicon Discretes product line, engineered specifically for high-frequency analog signal conditioning in portable wireless infrastructure and consumer radio systems.

FAQ

What is the recommended bias resistor value for 20 mA collector current?

For IC = 20 mA, set IBias = 2 mA using RBias = (VD − VEB)/IBias. With VD = 2 V and VEB ≈ 0.85 V, RBias ≈ 575 Ω. Standard 560 Ω or 620 Ω resistors yield IC within ±10% of target, verified per datasheet CR = 10 ±3.

Can the BGB540 be used in 5 GHz Wi-Fi applications?

At 5 GHz, |S21|² drops to 2.41 dB (≈275 mW gain), and noise figure rises above 3 dB. While functional as a low-gain buffer, it is not optimized for 5 GHz; dedicated 5 GHz LNAs like BGA725L6 show >10 dB gain and <2 dB NF at that frequency.

Is the SOT343 package lead-free and RoHS-compliant?

Yes-the BGB540 SOT343 package uses lead-free terminations and complies with RoHS Directive 2011/65/EU. Infineon's 2002 datasheet predates RoHS, but material declarations confirm Pb-free solderability and exemption status per Annex II.

How does thermal resistance affect maximum power dissipation?

Rth(JS) = 300 K/W means junction-to-solder-point temperature rise is 300 × (Pdiss) °C. At 20 mA and 2 V, Pdiss = 40 mW → ΔT = 12°C. Derate Ptot linearly above 75°C ambient to stay below 150°C Tj, limiting usable IC to ~50 mA at 100°C TA.