Microwave Ferrites, Coaxial & Dielectric Resonators : Ask now !

To meet the increasingly demanding demand for coaxial resonators, dielectric resonators, and ferrites intended for the isolator and circulator subsystems used in radio communication systems, integrated circuits, amplifiers, and switches.


Exxelia offers a wide range, including:

Coaxial resonators :

Coaxial resonatorsResonators generally used in filters, duplexers, DRO's, and VCO's over a wide frequency range: 300 MHz to 6 GHz. They are available in several dimensions: 2x2, 4x4, 6x6, and up to 12x12 mm, offering the best compromise between impedance, Q factor, and resonance frequency.

 

 

Dielectric resonators :

Dielectric resonatorsThe dielectric resonators are designed to replace resonant cavities in microwave functions such as filters and oscillators. Exxelia, with the support of the ESA and CNES, has developed the E7000 series which offers narrow bandwidth with reduced size. The E7000 dielectric resonator is based on Ba-Mg-Ta materials which combine ultra-high quality factor and the possibility to obtain all temperature coefficients on request. E7000 presents the high performances required for space use in the frequency range of 5 to 32 GHz and ensures up to Qxf > 250,000 at 10 GHz. As one of the few manufacturers producing its own raw materials, Exxelia perfectly masters the production of dielectric resonators. Encouraged by the success of this new range, Exxelia is now able to supply larger batches (up to 20 kg of powder) while retaining the same product properties.

 

Ferrites :

Microwave ferritesFerrites are magnetic materials used in a variety of applications. They are particularly effective in suppressing electromagnetic interference and noise in high-frequency applications, making them indispensable for modern communication systems.

Ferrites are offered in disc, triangle, or specific designs. These materials are based on Exxelia formulations, offering low deltaH (ΔH) conducive to reducing IMD. Their combination with a dielectric material allows for a wide choice of composites (FDA) to miniaturize isolator/circulator designs.

Exxelia's ferrites are distinguished by their exceptional quality and superior performance. These ferrites are made from high-quality materials and benefit from state-of-the-art design and manufacturing processes. They have been tested for use in demanding environments and have demonstrated exceptional reliability in applications up to 40 GHz.

Contact us to help you choose the ferrites that best suit your needs.

Published on 30 Mar 2023 by Stephane PERES

Countering Threats from Transients in Magnetics

Understanding Electrical Transients in Magnetics Electrical transients are sudden, short-duration spikes in voltage or current. They can arise from various sources such as lightning strikes, switching operations, or inherent instabilities within the system. These transients can cause severe stress on magnetic components, leading to potential malfunctions or catastrophic failures.   Causes of Electrical Transients Electrical transients can originate from external factors like environmental conditions or input/output operations. Internally, they can be caused by the natural response of the system's reactive components: resistors, inductors, and capacitors. These components, governed by the laws of physics, react to changes in state variables, resulting in oscillations, amplification, or decay of signals.   Effects on Magnetic Components Magnetic components, such as transformers and inductors, are particularly susceptible to transients. For instance, transformers can exhibit parasitic components that affect their response to sudden voltage or current changes. These parasitic elements can cause amplification, oscillation, or even breakdown under transient conditions.   Mitigating Transient Threats Effective mitigation of transient threats involves understanding the behavior of magnetic components under dynamic conditions and implementing design strategies to counteract these effects.   Component Functions and Response Resistors: Dissipate energy to manage power levels. Inductors: Generate opposing voltages to slow current changes. Capacitors: Absorb or release charge to stabilize voltage changes. The induced voltage and current in inductors and capacitors are inversely proportional to the circuit's time constant. A smaller time constant means faster energy transfer, which can lead to higher transient voltages or currents.   Transformer Design Considerations Transformers must be designed to handle dynamic impedance transformations and provide necessary isolation. Realistic transformer models must account for parasitic components, which can significantly influence their behavior during transients. High voltage transformers, for instance, are prone to series resonance due to leakage inductance and self-capacitance, leading to oscillations and potential saturation.   Practical Mitigation Techniques High Bandwidth Instruments: Use to detect latent transient amplification and persistent ringing during normal operations. Worst Case Analysis: Evaluate bias currents and flux density for worst-case scenarios, including maximum voltage and temperature conditions. Current Transformer Verification: Ensure that protection circuits can detect transient overcurrents despite reduced output due to saturation. Residual Magnetization Control: Verify that residual magnetization does not impair operation, ensuring sufficient headroom for magnetization. Design of Experiments (DOEs), Risk Reduction Tests (RRTs), and Accelerated Stress Tests (ASTs): Implement these throughout the design stages to mitigate risks effectively. Protective Components: Use components like MOVs (Metal Oxide Varistors) to safeguard circuits from lightning-induced transients.   Countering threats from transients in magnetics requires a thorough understanding of the underlying causes and the implementation of robust design strategies. By employing high bandwidth detection instruments, performing worst-case analyses, and integrating protective measures, engineers can significantly reduce the risk of transient-induced failures in magnetic components. Adopting a proactive approach to design and testing ensures the resilience and reliability of electrical systems in the face of transient threats.