SMA Feedthroughs for Vacuum Applications

Based on a simple coaxial configuration, SMA feedthroughs are ideal for high-frequency signal transmission applications such as radio communications and microwave systems. Their low noise capacities and low electrical impedance (50Ω) have enabled SMA coaxial feedthroughs to excel in highd and ultra-high vacuum (HV/UHV) processes.

Vacuum feedthrough connectors perform a range of functions in HV/UHV applications, but they must first satisfy some fundamental requirements. The connector must be hermetically sealed and shielded from peripheral electromagnetic interference. Materials used in the feedthrough’s construction must be rated for vacuum compatibility and high-performance in severe temperatures (ranging down to the cryogenic regime). Finally, the component must enable signal transmission at process-specific frequencies.

At Allectra, we develop and supply SMA feedthroughs that exceed these basic parameters for success. Our high vacuum coaxial feedthroughs are the first-choice solution for high-frequency signal processes in HV/UHV conditions.

What is a SMA Feedthrough?

SMA feedthroughs, also known as SubMiniature version A connectors, were first developed in the 1960s, combining a coaxial cable with a minimalistic screw-type interface. With low electrical impedance and a single thread coupling, SMA connectors proved ideal for antenna connections due to their inherent radiofrequency compatibility.

SMA feedthroughs offer good performance for signals ranging from DC to approximately 18 gigahertz (GHz) and are chiefly employed in HV/UHV applications for signal processing in this bandwidth. Their electronic performance is empowered by their strong physical construction, comprising high durability metal components in either grounded or floating configurations.

SMA Feedthroughs from Allectra

At Allectra, we offer a range of SMA coaxial feedthroughs for high-frequency signal transmission in vacuum conditions. Our primary product lines are the 242-SMA 50,  242-SMA-D18G, and the 242-SMAD27G with a wide range of configurations available to suit specific end-user objectives.

Starting with the 242-SMA 50, this range of miniature coaxial connectors offers true 50 Ω impedance with frequency ratings from DC to 6.5 GHz. They are available in single- and double-sided variations, with either grounded or floating shield configurations with up to four male connectors mounted onto a single flange as standard. The 242-SMADF50-C40, for instance, is a double-sided, floating shield connector for up to 6.5 GHz. The 242-SMA D18G C40-4, meanwhile, has four double-sided high-frequency SMA connectors on a single flange each rated to 18GHz. Finally, the new 242-SMAD27G harnesses SuperSMA technology to offer a staggering 27GHz frequency with lowest signal damping.

The advantage of double-sided connectors is in-vacuum the feedthrough can be connected directly to a standard Allectra in-vacuum cable from the 380-SMA range.

Thanks to Allectra’s advanced manufacturing capabilities it is also possible to increase the number of SMA connectors on one flange or combine them for instance with Allectra’s range of Sub-D feedthroughs.

If you would like to learn more about our full range of SMA feedthroughs, simply contact a member of the Allectra team today.