About Dielectric Varactors

Tecdia’s surface-mount dielectric varactors are made with a unique Tecdia proprietary voltage controllable dielectric and are designed for controlling impedance in a wide variety of applications operational up to millimeter-wave frequencies.  Some common applications for the varactor are Tunable Phase Shifters, Tunable Matching Networks, Tunable Filters, and Voltage Controlled Oscillators (VCOs).  Besides a selection of standard part numbers, we support custom varactor requests and can tailor capacitance, size, metallization, and other specifications as requested.  Please contact Tecdia for samples requests and questions regarding dielectric varactors.

Dielectric Varactor RF Simulation Models

In collaboration with Tecdia, Modelithics is adding RF simulation models for Tecdia’s dielectric varactors to their vast online model database.  These models will be made compatible with Keysight ADS, Genesys, and Cadence AWR. The full models for the first selection of standard part numbers will be available in July 2022 through the Modelithics Web Portal.  Please contact Tecdia for inquiries regarding dielectric varactor models.

Part Number Description

 http://165.227.4.187/products/hf/detail/slc/tunable-dielectric-capacitor/

Varactor Specifications

Features

• Low ESR
• >60dbm IP3 @ 14GHz
• >2W Power Handling @ 6GHz
• <50μs Switching Speed
• 0V capacitance of 0.1pF or more
• 0201 SMT Solderable form factor

Markets

Application Examples

5G Hybrid Beam Forming Antenna with Analog Phase Shifting

Dielectric Varactors can be implemented in phase shifters to control the phase of individual antenna elements on an antenna array. Through phase control of each antenna element a focused signal beam can be created and maneuvered. Many applications in 5G, including beam forming, require many channels to transmit simultaneously which can cause unwanted perturbances in devices with poor linearity.  Dielectric varactors linearity, defined by the IP3 parameter, is over 1000 times better than that of varactor diodes, essentially removing noise caused by non-linearity and making Tecdia’s Varactors ideal for applications such as 5G small cell and macro cell antenna.

High Frequency and Low Phase Noise VCO

Voltage Controlled Oscillators (VCOs) are devices that utilize varactors to generate signals of a specified frequency range. The use of dielectric varactors reduces the insertion loss and therefore reduce the VCO’s overall phase noise. Also, unlike varactor diodes, dielectric varactors act as variable capacitors when biased in either direction with the capacitance shift symmetric around 0V.  This symmetry reduces overall components and simplifies circuits since the designer no longer needs to account a varactor diodes forward biased short mode.  These advantages allow for higher frequency and lower phase noise VCOs than what has been possible with varactor diodes.