Diodes Incorporated ZMV833ATC

Overview

ZMV833ATC from Zetex Semiconductors is a silicon hyperabrupt varactor diode optimized for voltage-controlled frequency tuning in precision oscillators. It delivers 33.0 pF nominal capacitance at 2 V, 5.0–6.5 capacitance ratio (C₂/C₂₀), ≥200 Q at 50 MHz, and ultra-low reverse leakage (200 pA typ.), enabling low-phase-noise VCXO/TCXO designs in wireless infrastructure and mobile radio front-ends.

For engineers reviewing the ZMV833ATC datasheet, ZMV833ATC pinout, ZMV833ATC application, or ZMV833ATC equivalent, key selection criteria include its 25 V reverse breakdown rating, −55 °C to +150 °C operating range, SOT23 package compatibility, and verified hyperabrupt CV slope for steep tuning response in compact RF modules.

Technical Context

ZMV833ATC employs a hyperabrupt junction profile engineered to produce a steep, linearized C–V curve-critical for minimizing tuning nonlinearity and phase noise in voltage-controlled crystal oscillators. Its capacitance varies from ~36.3 pF at 2 V to ~5.6 pF at 20 V (C₂/C₂₀ ≥ 5.0), with tight process control ensuring ±5% unit-to-unit CV matching across production lots.

The device operates as a voltage-variable reactance element in resonant tank circuits, where applied DC bias modulates oscillator frequency without introducing significant loss or harmonic distortion. Its 200 pA typical IR at VR = 20 V directly supports sub-radian phase noise performance in 1–100 MHz reference clocking applications.

Key Specifications

Pinout & Package

ZMV833ATC is housed in a standard SOT23 plastic surface-mount package (JEDEC TO-236AB), with cathode-marked lead configuration and 1.9 mm × 1.3 mm footprint. Thermal resistance θ_JA is 370 °C/W; maximum power dissipation is 330 mW at T_amb = 25 °C.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMV2023-011LF and BBY52-02W, ZMV833ATC offers optimal balance of capacitance (33 pF), tuning ratio (≥5.0), and Q (≥200) for 10–50 MHz VCXOs requiring low-phase-noise and production-calibration efficiency-making it preferred for telecom-grade timing modules.

Availability

ZMV833ATC is available at Aetrix Electronics and suitable for VCXO design, TCXO compensation, and mobile radio VCO development requiring stable component supply, consistent CV matching, and RoHS-compliant SMT assembly.

Supply support for ZMV833ATC 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 plc was a UK-based ISO 9001/TS16949-certified manufacturer specializing in high-performance analog and RF discrete semiconductors before its acquisition by Diodes Incorporated in 2008.

ZMV833ATC belongs to the 830 series hyperabrupt varactor family, designed specifically for low-phase-noise frequency control in wireless infrastructure, precision timing, and portable communications equipment.

FAQ

What is the maximum recommended reverse voltage for continuous operation?

ZMV833ATC has a 25 V minimum reverse breakdown voltage and is rated for continuous operation up to 20 V reverse bias. Exceeding 20 V risks irreversible junction damage due to avalanche conduction, especially above 85 °C ambient. Derating to 15 V is advised for reliability-critical 15-year lifetime applications.

How does temperature affect capacitance stability?

Capacitance exhibits a positive temperature coefficient of +300 to +400 ppm/°C at 3 V bias. Over −40 °C to +85 °C, this causes ~5 % total C shift, necessitating active or passive compensation in TCXOs. The effect is linear and repeatable, enabling accurate modeling in oscillator simulation tools.

Can ZMV833ATC be used in AC-coupled tuning configurations?

No-ZMV833ATC must operate with unidirectional reverse bias. AC coupling introduces forward conduction during negative half-cycles, causing irreversible parameter shift and increased leakage. A DC-blocking capacitor may be placed in series only if a fixed reverse bias is maintained across the diode at all times.

Is the SOT23 package lead-free and RoHS compliant?

Yes-ZMV833ATC was manufactured under Zetex's green compliance program and meets EU RoHS Directive 2011/65/EU requirements. The SOT23 package uses matte tin (Sn) plating over copper leadframe, with no lead, cadmium, mercury, hexavalent chromium, PBB, or PBDE content-verified per IEC 62321 testing.