INDUSTRY COMPONENT

Varactor Diode

Varactor diode is a semiconductor device with voltage-dependent capacitance used for electronic tuning in voltage-controlled oscillators.

Component Specifications

Definition
A varactor diode, also known as a varicap or tuning diode, is a specialized semiconductor diode designed to exploit the voltage-dependent capacitance of a reverse-biased p-n junction. Its capacitance varies inversely with the applied reverse voltage, making it essential for frequency modulation, phase-locked loops, and tuning circuits in communication systems.
Working Principle
The varactor diode operates on the principle of a reverse-biased p-n junction, where the depletion region width changes with applied voltage, altering the junction capacitance. In a voltage-controlled oscillator (VCO), this capacitance variation adjusts the resonant frequency of the LC tank circuit, enabling precise electronic frequency control without mechanical components.
Materials
Silicon (Si) or Gallium Arsenide (GaAs) semiconductor wafers with doped regions (p-type and n-type), metal contacts (aluminum or gold), and ceramic or plastic packaging.
Technical Parameters
ParameterTypical rangeNotes & selection driver
Q Factor50-200 at 1 MHz
Package TypeSMD (e.g., SOD-323, SOT-23)
Tuning Ratio2:1 to 10:1
Reverse Voltage1-30 V
Capacitance Range1-100 pF
Operating Temperature-55°C to +125°C

Ranges are indicative industry figures for RFQ preparation, not a supplier commitment. Confirm every value and standard with the legal manufacturer before ordering.

Standards
IEC 60747, JEDEC JESD22

Parent Products

This component is used in the following industrial products

Engineering Analysis

Risks & Mitigation
  • Thermal drift affecting capacitance stability
  • Voltage overstress leading to breakdown
  • Manufacturing defects causing parameter variations
FMEA Triads
Trigger: Excessive reverse voltage
Failure: Junction breakdown and permanent damage
Mitigation: Implement voltage clamping circuits and adhere to specified voltage limits.
Trigger: High operating temperature
Failure: Capacitance drift and reduced tuning accuracy
Mitigation: Use thermal management and select diodes with low temperature coefficients.

Industrial Ecosystem

Compatible With

Typical Suppliers & Equivalents

Compliance & Inspection

Tolerance
Capacitance tolerance typically ±5% to ±20%, depending on grade
Test Method
Capacitance-voltage (C-V) measurement at specified frequencies and temperatures per IEC 60747 standards.

Procurement Evaluation Criteria

A practical evidence checklist for RFQ preparation and supplier evaluation.

Technical documentation
Request current drawings, revision history, and a signed specification sheet.
Manufacturing capability
Verify equipment lists, process limits, capacity, and representative production evidence.
Inspection readiness
Confirm test methods, calibrated equipment, sampling plans, and traceable reports.
Supplier transparency
Check the legal entity, factory address, ownership, certifications, and direct contacts.

CNFX does not score or rank suppliers. Buyers must verify all claims and documents with the legal manufacturer before ordering.

Manufacturers of Varactor Diode

Manufacturer profiles associated with Varactor Diode.

Sourcing Varactor Diode from China?
Tell us your specification and target quantity — we will match it against manufacturer records and come back with the factories that fit.
Request manufacturers We manufacture this

Manufacturer listings support early research and capability understanding. They are not certification, ranking, or transaction guarantees.

Related Components

Dielectric Layer
Insulating layer in surface mount capacitors that stores electrical energy through polarization.
Optical Window
Transparent optical component for light transmission in polycarbonate lens housings
PCB Substrate
PCB substrate is the foundational insulating layer that provides mechanical support and electrical connectivity for electronic components in high-speed memory modules.
Edge Connector
Edge connector is a printed circuit board (PCB) connector that mates with the edge of another PCB, commonly used in high-speed memory modules for reliable electrical connections.

Frequently Asked Questions

What is the main function of a varactor diode in a VCO?

It provides voltage-dependent capacitance to electronically adjust the oscillator's frequency, enabling stable and tunable signal generation.

How does reverse voltage affect a varactor diode?

Increasing reverse voltage widens the depletion region, reducing capacitance, which allows precise frequency control in tuning applications.

Data Basis

Editorial classification, named public sources where available, and source-reviewed manufacturer records. See the editorial policy.

Preliminary Technical Classification
This page supports structured research, RFQ preparation, and supplier evaluation. It does not replace buyer-led supplier qualification, standards review, or technical approval.

Request Manufacturing Insight for Varactor Diode

Thank you. Your request has been sent. We'll respond within 1–3 business days.
Sorry, we couldn't send your message. Please try again, or email us at contact@cnfx.com.
UVLO (Under-Voltage Lockout) Circuit Via
Get QuotesChat