Infineon Technologies BB659CH7903XTMA1

Overview

BB659CH7903XTMA1 from Infineon Technologies is a silicon hyperabrupt junction varactor diode in SC79 (SOD-323-compatible) package, optimized for VHF TV/VTR tuner frequency tuning. It delivers 36.5–42 pF capacitance at 1 V reverse bias, 2.4–2.75 pF at 28 V, and a measured capacitance ratio CT₁/CT₂₈ of 14.2–15.3 at 1 MHz.

For engineers reviewing the BB659CH7903XTMA1 datasheet, BB659CH7903XTMA1 pinout, BB659CH7903XTMA1 application, or BB659CH7903XTMA1 equivalent, key selection criteria include its 0.6 nH series inductance, 0.6 Ω typical series resistance at 470 MHz, ±0.5% capacitance matching across 4-diode sequences, and RoHS-compliant Pb-free construction.

Technical Context

This varactor operates as a voltage-controlled capacitor in resonant tank circuits, where reverse bias voltage directly modulates junction depletion width to tune oscillator or filter center frequency. Its hyperabrupt doping profile ensures near-linear C–V slope over 1–28 V, enabling wide-band VHF tuning with minimal distortion.

The device uses an "in-line" matching assembly process that guarantees tight capacitance uniformity across production lots-critical for multi-stage tuners requiring matched diode banks. Its SC79 package provides low parasitic inductance (0.6 nH) and resistance (0.6 Ω), preserving Q-factor above 470 MHz.

Key Specifications

Pinout & Package

BB659CH7903XTMA1 is housed in the SC79 surface-mount package (JEDEC TO-236AB), a miniature 2-pin plastic case measuring 1.7 × 0.8 × 0.7 mm with cathode marked by a laser-etched bar. The package features low thermal resistance and optimized pad layout for RF grounding.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BB659C-02V, BB659CH7903XTMA1 offers identical performance with updated date-code and marking compliance; versus BB639C, it delivers 30% higher low-voltage capacitance and 25% lower series inductance-directly enabling wider VHF tuning range and improved high-frequency stability.

Availability

BB659CH7903XTMA1 is available at Aetrix Electronics and suitable for VHF TV tuners, professional VTR systems, FM radio front-ends, and wireless microphone transmitters requiring stable component supply and tight parametric matching.

Supply support for BB659CH7903XTMA1 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 industrial control ICs and discrete devices.

BB659CH7903XTMA1 belongs to Infineon's BB6xx varactor family, engineered specifically for high-uniformity, wide-tuning-ratio RF frequency synthesis in broadcast and professional audio/video equipment.

FAQ

What is the maximum recommended reverse voltage for continuous operation?

The absolute maximum DC reverse voltage is 30 V at TA = 25°C, with a peak rating of 35 V for transient conditions where series resistance R ≥ 5 kΩ. Exceeding 30 V DC risks irreversible junction breakdown due to avalanche multiplication, especially above 85°C where IR rises to 200 nA.

How does temperature affect capacitance stability?

Capacitance exhibits a negative temperature coefficient (TCC) ranging from –3×10⁻⁴ to –5×10⁻⁴ /°C depending on bias voltage. At VR = 1 V, TCC ≈ –4.2×10⁻⁴ /°C; at VR = 28 V, it reduces to –1.8×10⁻⁴ /°C. This must be compensated in precision VCOs using thermistor networks or digital calibration.

Can BB659CH7903XTMA1 replace BB659C-02V in existing designs?

Yes-BB659CH7903XTMA1 is a direct form-fit-function replacement for BB659C-02V. Both share identical SC79 packaging, electrical specifications, and in-line matching process. The "H7903XTMA1" suffix reflects Infineon's internal lot and revision coding; no design changes or requalification are required.

Is this device suitable for use in life-support systems?

No. Infineon explicitly prohibits use of BB659CH7903XTMA1 in life-support devices or systems-including implantables or critical safety monitors-without prior written approval. Its qualification covers industrial and consumer broadcast applications only, with no extended reliability testing for medical-grade fault tolerance.