Diodes Incorporated ZC832BTC

Overview

ZC832BTC from Zetex Semiconductors is a silicon hyperabrupt varactor diode optimized for voltage-controlled frequency tuning in precision oscillators and RF filters. It delivers 22.0 pF nominal capacitance at 2 V, 5.0–6.5 capacitance ratio (C₂/C₂₀), ≥200 Q at 50 MHz, ≤200 pA reverse leakage, and operates up to 25 V reverse bias - enabling low-phase-noise VCXO designs in wireless infrastructure.

For engineers reviewing the ZC832BTC datasheet, ZC832BTC pinout, ZC832BTC application, or ZC832BTC equivalent, key selection criteria include its hyperabrupt CV slope for steep tuning response, SOT23 package compatibility with high-density RF layouts, guaranteed C₂/C₂₀ ≥5.0, and verified low IR performance critical for oscillator phase noise floor.

Technical Context

The ZC832BTC employs a silicon hyperabrupt junction profile engineered to produce a steep, linearized voltage-to-capacitance transfer function - essential for stable frequency pulling in TCXOs and VCOs. Its CV curve is tightly controlled across production lots, with ±5% capacitance tolerance at VR = 2 V and f = 1 MHz.

Designed for RF signal path tuning, it maintains Q ≥200 at 50 MHz under 3 V bias, minimizing insertion loss in bandpass filter resonators and oscillator tank circuits. The device's temperature coefficient of capacitance (300–400 ppm/°C) is characterized and compensated in reference designs for ±0.5 ppm stability over –30°C to +85°C.

Key Specifications

Pinout & Package

Supplied in SOT23 surface-mount package (JEDEC TO-236AB), 3-terminal configuration with anode, cathode, and case (cathode-marked). Package dimensions: 2.67–3.05 mm × 1.20–1.40 mm × 0.95 mm height; thermal resistance θ_JA ≈ 300°C/W.

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, ZC832BTC offers the optimal balance of tuning range (C₂/C₂₀ ≥5.0), low-leakage stability (≤200 pA), and proven 25 V rating - making it preferred for industrial-grade VCXOs where long-term bias stability and wide temperature operation are critical.

Availability

ZC832BTC is available at Aetrix Electronics and suitable for VCXO modules, RF front-end filters, mobile radio transceivers, and pager IF stages requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for ZC832BTC 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 analog semiconductor manufacturer specializing in high-performance discrete devices before its acquisition by Diodes Incorporated in 2008.

The 830 series varactors were developed specifically for precision frequency control in wireless timing systems - emphasizing tight CV matching, low phase noise contribution, and robust SMT packaging for RF assembly reliability.

FAQ

What is the maximum recommended reverse voltage for continuous operation?

The ZC832BTC has an absolute maximum reverse voltage rating of 25 V, with derating advised above 125°C ambient. For reliable long-term operation in VCXO applications, Zetex recommends limiting VR to ≤20 V to maintain reverse leakage below 2 nA and avoid accelerated junction degradation.

Does ZC832BTC require external bias decoupling in VCO designs?

Yes - a minimum 100 nF ceramic capacitor must be placed between anode and ground within 2 mm of the SOT23 pad. This prevents RF feedback into the tuning voltage rail and suppresses parasitic oscillation, as confirmed in Zetex Application Note AN-830-3 for VCO layout best practices.

Is the SOT23 package lead-free and RoHS-compliant?

Yes - per Zetex Issue 11 datasheet (January 2007) and Diodes Incorporated product continuity documentation, ZC832BTC is RoHS-compliant, lead-free, and halogen-free. The SOT23 termination uses matte tin plating over nickel barrier, qualified to JEDEC J-STD-020 moisture sensitivity level 1.

How does temperature affect capacitance tuning linearity?

Capacitance decreases linearly with rising temperature at 300–400 ppm/°C, causing a predictable downward shift in resonant frequency. In TCXO designs, this is compensated using NTC thermistors or digital lookup tables - Zetex provides full CV vs. temperature curves in Figure 5 of the 830 series datasheet.