Mini-Circuits integrate Menlo Microsystems’ Ideal Switch technology into their MEM-SP4T A18 absorptive switch to increase performance and address new wireless applications
Mini-Circuits has a long history of supplying semiconductors and electro-mechanical relay (EMR) based switches for telecoms, defence, automotive, and industrial applications.
However, as wireless technology applications become faster, more complex, miniaturised, and more energy efficient, the performance demands placed the constituent components integrated into host systems increases. For example, the latest high-volume semiconductor testing, satellite communications, and agile RF signal routing applications require low-loss, ultra-fast and extremely reliable switches and these requirements cannot be fully addressed by solid state switches which are inherently lossy or EMRs with their limited life expectancy and relatively low switching speed.
Challenge
Faced with these fundamental bottlenecks of existing switch technologies, Mini-Circuits approached switch developer Menlo Microsystems to explore if a collaboration could enhance Mini-Circuits’ product portfolio with a new absorptive RF switch without the losses associated with solid-state switches or the limited life expectancy and speed of EMRs, able to meet the demands of cutting-edge wireless applications.
Technology: the Ideal Switch
Significant research has been conducted in recent years to develop a new category of switch, based on micro-electromechanical systems (MEMS) technology able to address size, weight, power, frequency coverage, life expectancy, and linearity design compromises – resolving them in a single device. What has emerged is an evolved switch platform that is able to switch AC/DC and RF power, therefore offering superior performance in a much smaller physical package at a lower cost. It is based on a proprietary manufacturing process and innovative materials science originally developed at General Electric (GE) that is now being further developed and commercialised by Menlo Microsystems as the Ideal Switch.
Combining semiconductor manufacturing techniques with a micro-mechanical actuator, this new generation of switch achieves practically infinite isolation when OFF, and close to Zero Ω when ON, eliminating the need for bulky, heavy heatsinks. It consists of three fundamental parts: a durable beam made of proprietary alloys, a low resistance contact, and a low loss electrostatic gate. It has universal signal coverage, able to carry AC/DC and RF signals with linear performance from DC to > 50GHz. The miniaturised, paired-back design and innovative materials make it extremely fast, highly reliable, and durable – switching in under 10μs, with a life expectancy exceeding billions of operations. These qualities made the Ideal Switch very attractive to Mini-Circuits in their mission to design an advanced switch without the performance limitations of other technologies.
Process
It was important for Mini-Circuits to be able to offer a new switch to market that could be easily adopted by their customer base and utilised in existing wireless systems. Therefore, the approach from Mini-Circuits was to take the design, form-factor, and interfaces of an existing EMR-based switch and adapt it to create their first MEMS-based switch. The design teams of Mini-Circuits and Menlo Micro collaborated on this project, holding frequent design reviews and Mini-Circuits were able to benefit from Menlo’s excellent applications engineering support team to facilitate the integration.
Product overview
What emerged was Mini-Circuits’ MEM-SP4T-A18, an absorptive SP4T switch with high speed, high linearity and high reliability of a semiconductor switch and power handling comparable to a mechanical one.
Life expectancy increased from millions of operations to three billion exceptionally reliable switch cycles, making it particularly useful for ground station satellite communication applications where reliability is of paramount importance. Furthermore, the switching time decreased from around 20ms to 15us, which significantly reduces test time when applied to semiconductor ATE where a huge volume of tests is required. The ultra-fast DC and RF switching opens new, near real-time applications for low-latency signal routing, for example antenna line feeds, agile beamforming, and industrial applications such as fast RF switches in quantum computing. The improved DC passing capability up to 9V, 500mA allows the switch to be used in antenna feeds and high-power amplifiers without the need for separate DC feeds.
The USB daisy-chain control interface with “dynamic addressing” simplifies control integration, allowing up to 25 compatible switches to be combined into a Master / Slave chain configuration. Additionally, the switch is powered by the USB interface rather than needing a separate 24V DC power supply.
Conclusion
The enhancement to Mini-Circuits’ product portfolio enabled by their first MEMS-based switch complements their existing semiconductor and EMR products, adding a competitively differentiated solution that delivers higher performance and greater reliability, while addressing more demanding use cases. This is particularly beneficial as modern wireless communications demand systems that are faster, smaller, and more reliable – trends that continue to accelerate – allowing Mini-Circuits to expand into additional markets.
Mini-Circuits Global Product Marketing Manager for Product Line Test Solutions and High-Power Amplifiers, Angelo Andres, summed up the collaboration as follows: “Our work with Menlo Micro’s Ideal Switch technology has enabled us to fully develop our MEM-SP4T-A18 absorptive SP4T switch, which completes our broad portfolio of switch test products and modules to address a wide range of wireless communication applications.”
The experience has demonstrated both the ease of integration and the robust reliability of the Ideal Switch. Furthermore, because the switch is the most fundamental building block of electronic modules and systems, it opens up future opportunities to extend its benefits into a vast range of products such as multiplexers, attenuators, phase shifters and filter banks – ultimately meeting current and future demands for high performance and reliability in next-generation wireless communications.
