Diodes Incorporated ZMV934ATA

Overview

ZMV934ATA from Zetex Semiconductors is a 12 V hyperabrupt silicon varactor diode in SOT-23 package, designed for voltage-controlled frequency tuning in oscillator circuits. It delivers 95.0 pF capacitance at 1 V, 40.0 pF at 2.5 V, and 25.0 pF at 4 V reverse bias, with minimum Q of 80 at 50 MHz and typical reverse leakage of 200 pA - enabling low-phase-noise VCXO/TCXO designs for wireless infrastructure.

For engineers reviewing the ZMV934ATA datasheet, ZMV934ATA pinout, ZMV934ATA application, or ZMV934ATA equivalent, key selection criteria include its octave-tuning range (0–6 V), hyperabrupt C-V slope (300–400 ppm/°C tempco), low IR, high Q at RF frequencies, and SOT-23 footprint compatibility with compact timing modules.

Technical Context

This varactor operates as a voltage-dependent capacitor in resonant tank circuits, where applied reverse bias modulates junction capacitance via hyperabrupt doping profile. Its C-V curve is tightly controlled across production lots to ensure predictable tuning linearity in precision oscillators.

Designed for RF tuning up to 50 MHz, it maintains stable Q ≥80 at VR = 4 V and exhibits minimal temperature drift (300–400 ppm/°C) - critical for maintaining frequency stability in TCXOs under thermal variation.

Key Specifications

Pinout & Package

SOT-23 surface-mount package: 3-pin, single-anode/dual-cathode configuration (cathode common to pins 1 & 3); body dimensions 2.9 × 1.3 × 1.0 mm (L × W × H).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMV1232-011LF and BBY52-02W, ZMV934ATA offers optimal balance of octave tuning range, low IR, and SOT-23 manufacturability - making it preferred for cost-sensitive, high-volume 10–100 MHz VCXO/TCXO modules where phase noise and thermal stability are co-constrained.

Availability

ZMV934ATA is available at Aetrix Electronics and suitable for VCXO modules, TCXO reference oscillators, wireless transceiver local oscillators, and pager frequency synthesizers requiring stable component supply across automotive-grade and industrial temperature ranges.

Supply support for ZMV934ATA 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

Zetex Semiconductors (now part of Diodes Incorporated) specialized in high-performance analog and RF discrete semiconductors, with emphasis on precision timing, signal conditioning, and power management components.

ZMV934ATA belongs to the ZC/ZMV/ZV93x hyperabrupt varactor series - engineered specifically for low-phase-noise, temperature-stable frequency control in communication infrastructure and portable radio equipment.

FAQ

What is the maximum recommended reverse voltage for continuous operation?

The absolute maximum reverse voltage is 12 V, but for reliable long-term operation in TCXO applications, Zetex specifies derating to ≤8 V to maintain IR <100 nA and avoid accelerated junction degradation. Operation at 6 V achieves full octave tuning while preserving phase noise performance and lifetime reliability.

Does ZMV934ATA have a specified capacitance tolerance at 1 V?

Yes - the datasheet specifies capacitance at 1 V as 95.0 pF with ±10% tolerance (85.5–104.5 pF) across the production lot. This tight tolerance enables consistent pullability in mass-produced VCXOs without individual unit calibration.

Can ZMV934ATA be used in series or parallel configurations?

It is configured as a single-anode/dual-cathode device in SOT-23; pins 1 and 3 are internally connected cathodes. Parallel use is not supported - the dual-cathode structure serves thermal and layout symmetry, not functional redundancy. Series connection is electrically invalid due to shared cathode node.

Is the SOT-23 pinout compatible with JEDEC standard SOT-23-3?

Yes - ZMV934ATA follows JEDEC MO-178AA outline: pin 1 (cathode), pin 2 (anode), pin 3 (cathode), with 0.95 mm pitch and 2.9 mm length. Footprint matches standard SOT-23 land patterns used in IPC-7351B Class L design rules.