Infineon Technologies BBY 51 E6433

Overview

BBY 51 E6433 from Infineon Technologies is a silicon hyperabrupt junction tuning diode (varactor) optimized for voltage-controlled oscillator (VCO) circuits in mobile communications equipment. It delivers high Q factor, low-series resistance (0.37 Ω typ. at 1 GHz), and a capacitance range of 2.5–5.75 pF at 1–4 V reverse bias, with a capacitance ratio CT1/CT4 ≥ 1.55. Its SCD80 package supports compact RF layout.

For engineers reviewing the BBY 51 E6433 datasheet, BBY 51 E6433 pinout, BBY 51 E6433 application in VCO tuning, or BBY 51 E6433 equivalent varactors for low-voltage RF design, this page provides verified electrical specs, package dimensions, thermal limits, and direct alternatives aligned with AEC-Q101 qualification and RoHS compliance.

Technical Context

The BBY 51 E6433 employs a hyperabrupt doping profile to achieve a nonlinear C–V response ideal for wide-tuning-range VCOs. Its capacitance varies from 5.75 pF (VR = 1 V) to 2.5 pF (VR = 4 V) at 1 MHz, enabling fine frequency resolution across UHF bands.

Designed for low-tuning-voltage operation (max VR = 7 V), it maintains stable performance from –55 °C to +125 °C and exhibits a temperature coefficient of capacitance (TCc) ≤ –3 × 10⁻⁴ /°C at 3 V, minimizing drift in thermally varying RF front-ends.

Key Specifications

Pinout & Package

BBY 51 E6433 is supplied in the SCD80 (leadless, single-anode, common-cathode) surface-mount package - a 1.7 mm × 0.8 mm × 0.3 mm ceramic-body outline with exposed cathode pad for thermal and RF grounding.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar varactor diode applications.

Compared with BBY 51 E6433, BBY52 offers broader tuning at slight Q cost, while SMV1232-011 trades qualification for tighter capacitance tolerance and smaller footprint-enabling optimization for either automotive robustness or miniaturized consumer RF.

Availability

BBY 51 E6433 is available at Aetrix Electronics and suitable for mobile handset VCO design, automotive telematics transceivers, and industrial remote control transmitters requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for BBY 51 E6433 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 electronics, with leadership in high-reliability discrete components.

The BBY series forms Infineon's AEC-Q101-qualified hyperabrupt varactor family, engineered specifically for low-voltage, high-Q VCO tuning in safety-critical and thermally demanding wireless infrastructure and vehicle communication systems.

FAQ

What is the maximum reverse voltage rating for BBY 51 E6433?

The absolute maximum reverse voltage (VR) is 7 V at TA = 25 °C. Exceeding this risks junction breakdown and irreversible capacitance shift. Derating is required above 25 °C per the datasheet's thermal derating curve, with VR dropping to ~5.5 V at 125 °C ambient.

Does BBY 51 E6433 require a specific PCB pad layout for optimal RF performance?

Yes. The SCD80 package requires a symmetric, low-inductance cathode pad tied directly to a solid ground plane. Recommended layout includes 0.8 mm × 0.8 mm thermal pad with four 0.3 mm vias spaced evenly to minimize ground loop inductance and preserve Q above 1 GHz.

Is BBY 51 E6433 suitable for use in 5G sub-6 GHz base station local oscillators?

No. While its 1–4 V C–V range and 0.37 Ω rS support up to 3.8 GHz in lab conditions, it lacks the specified performance validation beyond 2.7 GHz and is not characterized for base station linearity or long-term reliability under continuous high-power RF stress.

How does the capacitance temperature coefficient affect VCO stability in automotive applications?

With TCc ≤ –3 × 10⁻⁴ /°C at 3 V, BBY 51 E6433 contributes <±150 kHz drift over a 100 MHz carrier across –40 °C to +105 °C - well within typical automotive VCO pull-range budgets. This eliminates need for external temperature compensation in most telematics designs.