One of the summer’s projects was producing a video where our founder, Seyed Tabatabaei, shares his motivation for starting mmTron and the market need the company is filling. It provides a concise overview for those not familiar with mmTron or mmWave markets.

Takeaways?

mmTron’s ability to develop high power, high linearity, and high efficiency mmWave RFICs is extending the reach and data rates of fixed wireless access (FWA) and satellite communications (Satcom) systems.

The more than 47 products providing multiple circuit functions and growing number of customers clearly show mmTron’s differentiation.

As Seyed concludes, “This is an amazing time to partner with mmTron to be able to respond to this growing demand.”

We appreciate the video production skills of Chris Sheppard, Content Source.

mmTron’s co-founder and CEO, Seyed Tabatabaei, and Engineering Fellow, Mike Roberg, were interviewed by Eric Higham of Microwave Journal at this year’s IMS in Washongton, D.C. Watch the short interview to learn how mmTron is providing value to customers with high linearity, high power, and high efficiency power amplifiers for fixed wireless access and satellite communications systems.

We appreciate the opportunity to be interviewed by Microwave Journal and covered in their IMS 2024 Show Wrap Up article.

mmTron was started in 2020 to provide disruptive MMICs for mmWave applications. By disruptive, we mean significantly extending the performance of those key parameters that improve system performance.

Communications Care-Abouts

For communication systems, the parameters are data rate, link distance, and the attendant cost of the radio network. At the component level, the combined output power and linearity of the power amplifier in the transmitter drive the data rate and link distance. Longer links reduce the number of transmitters and repeaters and the resulting cost of the network.

Brute power, however, is not the goal, as saturating a semiconductor device to get higher power generates harmonics and intermodulation products. Power at a specified error vector magnitude (EVM) is the key metric, with the required EVM set by the modulation used by the communications system. The output power at this EVM becomes the metric for judging the quality of the power amplifier or transmitter.

The power consumption of the transmitter is also important, as it determines the heat sinking required to channel heat from the semiconductor devices. This thermal design is a major contributor to the weight and size of the transmitter, important because it can limit where the transmitter can be mounted and whether it can be carried and installed by one person. At the component level, the power-added efficiency of the power amplifier is the key metric for judging power consumption.

Historically, power amplifier designers focused on just two of these three metrics: output power, linearity, and power-added efficiency. Optimize the two most important parameters and accept the third, which was largely determined by the semiconductor technology, bias point, and matching circuits.

Market Need Meets Opportunity

Seeing the need to optimize all three became the goal for mmTron’s designers. They start with the choice of semiconductor technology for the application, then optimize the process, device bias points, matching circuit topology and element values. To achieve precision in the simulation — the goal is always first-pass design success — they had to improve their circuit and electromagnetic analysis tools and design flow. (Keysight published a case study on the electronic design automation (EDA) stack we used for the design of the TMC211, a 26 to 29.5 GHz power amplifier MMIC with 50 watts saturated output, which you can download here.)

Disruptive Performance

mmTron’s 37 to 41 GHz GaN power amplifier MMIC illustrates how this design philosophy and approach achieve disruptive performance. The first MMIC developed by mmTron, the TMC212 power amplifier was designed for the n260 5G band. With a 400 MHz 5GNR signal, it provides 27 dBm output power with just 1.8% EVM, truly state-of-the-art.

The three-stage MMIC has 23 dB small-signal gain and is matched to 50 Ω. It is nominally biased at +24 V on the drain, with a negative gate voltage adjusted to set the drain current to 400 mA. The TMC212 is offered in a 6 mm x 6 mm laminate QFN package. At 85°C ambient, the junction temperature of the GaN MMIC is below 140°C, which supports more than 10 million hours of reliable operation.

With its high linear power, the TMC212 is being used in fixed wireless access and “smart” repeaters. It’s one of a family of mmTron MMICs developed for the 5G NR bands (n257, n258, n259, and n261). Performance information on all mmTron’s devices are available on the Products page of our website.

Among the innovative products mmTron introduced last year, the active balun created a new product category. It serves as a bridge between the high-speed digital and microwave worlds, a key element as systems adopt direct RF sampling.

Functionally, the active balun is an interface for high-speed A/D and D/A converters. It preserves the digital converter’s dynamic range by providing low noise, high linearity, and wide bandwidth amplification.

A tutorial on active baluns written by Seyed Tabatabaei, mmTron’s founder, was recently published by 5G Technology World. Seyed discusses the performance requirements driving the designs and choosing the best semiconductor technology for implementation.

mmTron has introduced four initial products in the active balun family. Click on the links below to see the technical specs for each product:

TMC160-16 — Single Channel D/A Converter Interface
TMC161 — Single Channel A/D Converter Interface
TMC180-16 — Dual-Channel D/A Converter Interface
TMC181 — Dual-Channel A/D Converter Interface

2023 has been an incredible year for mmTron, as we announced our product-market strategy and unveiled more than 20 innovative products that extend the industry’s output power, linearity, efficiency, and bandwidth for Satcom, 5G, instrumentation, and aerospace/defense applications.

mmTron’s family of 5 W GaN power amplifiers (TMC152, TMC253, and TMC212) provide the highest linear power for the 5G FR2 bands from 22 to 41 GHz. The TMC211, TMC2111, and TMC2112 provide even higher linear power across 24.5 to 29.5 GHz: 40 to 50 W saturated power and >20 W linear power with an NPR of 19 dBc.

Our portfolio of eight distributed amplifiers addresses broadband applications from 20 to 160 GHz, achieving the highest gain-bandwidth products.

We also created a new product category: data converter interfaces for high-speed A/D and D/A converters. These interfaces provide a low noise, high linearity transition from the differential ports of the converters to the 50 Ω RF world. To get the best performance, we designed our own baluns and have released them as standalone products (TMC810, TMC811, TMC812, and TMC813).

mmTron exhibited at IMS in San Diego and EuMW in Berlin, and our capabilities have been featured by Microwave Journal, Microwave Product Digest, and everythingRF.

Thank you for your interest and contributions to making this an incredible year for mmTron.

The IEEE BiCMOS and Compound Semiconductor Integrated Circuits and Technology Symposium (BCICTS) just completed its sixth annual conference, 15–18 October, in Monterey, Calif. BCICTS is the marriage of the Compound Semiconductor IC Symposium (CSICS) and the Bipolar/BiCMOS Circuit and Technology Meeting (BCTM), which ran for 42 and 35 years, respectively, before joining to start BCICTS.

mmTron was one of seven companies exhibiting this year, along with five sponsors, to help underwrite the event. Co-founders Seyed Tabatabaei and Mona Molaasgari and Mike Roberg, Engineering Fellow, attended to take in the conference papers and share mmTron’s differentiated strategy for serving the mmWave market.

Mike has long served on the conference technical program committee (TPC) and served as the BCICTS publications chair this year. Next year, he’ll chair the TPC. His association with BCICTS gives him a good perspective on the technology and industry, so we asked Mike to share his impressions of the event:

“BCICTS attendees were greeted by beautiful weather and a fantastic technical program in Monterey.

The three excellent plenary talks highlighted the future directions of compound semiconductor technology. Tom Kazior (DARPA) gave an excellent talk on how 3D heterogeneous integration will be a key enabler for next generation RF systems. Building on this concept, Shahriar Shahramian (Bell Labs) discussed Bell Labs’ research efforts in E- and D-Band phased array development, which is enabled by glass interposer technology. Umesh Mishra (UCSB) wrapped up the plenary session with an excellent talk discussing how N-polar GaN offers significant promise for improving mmWave power density, which is becoming a bottleneck for many applications.

The exhibitor reception, held Monday evening, enabled the attendees to have substantive technical conversations with one another, so was well attended. With some 170 attendees, BCICTS is a smaller conference, which makes the engagement opportunities unique for exhibitors. Most attendees are directly involved with IC design, so the discussions are typically technical and detailed, which often identifies unique business opportunities for the exhibitors.

It was clear from the conference that mmWave systems are a hot topic. The challenges seemed to consistent across all the presented papers: consumed and dissipated power needs to be reduced while linearity and output power are increased. Oh, and don’t forget the integration challenges at mmWave, making a phased array, for example!

While these challenges are quite difficult, they are favorable for mmTron’s future due to our mmWave IC design expertise, which leads to products with world class power, power-added efficiency, and linearity. As GaN nodes continue being developed for mmWave (e.g., STARRY NITE, a program on the microelectronics roadmap of the Office of Undersecretary of Defense Research & Engineering), mmTron is well-positioned to offer GaN MMIC products exceeding 100 GHz with output power not previously achievable.

Fraunhofer’s presentation on advanced mHEMT technologies was one of the papers that was particularly impressive. It achieved MMIC amplifier performance beyond 700 GHz, which is astounding. They presented an integrated module for a synthetic aperture radar, with performance at 400 GHz, also impressive.

— Mike Roberg