Startup Intros ‘Most Advanced’ Multi-Gigahertz Timing and Clock Devices

Today, startup Mixed Signal Devices has announced its new MS11X0 oscillator and MS15X0 jitter attenuator families. The devices are aimed at addressing the demands of today’s most complex and high-speed computing and communications systems.

To learn more about the timing devices, I spoke with Avi Madisetti, CEO of Mixed Signal Devices.

AI Data Centers Driving Clock Performance Demands

According to Madisetti, there are numerous high growth markets—from wireless comms to aerospace and defense—that require the most challenging specs when it comes to timing. But it’s really AI in data centers that are driving clock performance.

AI is driving clock performance in the data center and clocks could become a bottleneck.
 

In AI data centers, there’s a whole bunch of hardware that is rapidly growing in speed and complexity. “The bottlenecks have always been the processing where you can throw more GPUs or servers at something,” said Madisetti. “But when you have a lot of processing power, the I/O bottlenecks come into play. That's where the SerDes, PCI Express, and NVLinks come into play.”
 

For those interconnects, clocks were always a player in the background, but they're beginning to get much more important. “You'll slowly start seeing a clock bottleneck,” says Madisetti. “Speeds have increased by a factor of 10X already in the last decade. Now you see Ethernet fabric switches going from 51 terabits per second, to 102 Tbps, and more. They’re doubling every few years. People are also talking higher modulation schemes, such as PAM 6 or PAM 8.” “

“At the end of the day, you're going to need better clocks to support those. And today’s legacy clock devices have not kept up in performance.”

Between the Two Approaches

With all that in mind, Mixed-Signal Devices decided to position itself between the two different ends of the clocking industry. On one side are the set of players with devices based on crystal oscillators. And the other end are vendors with clock chips centered around phase-locked loop (PLL) technology. Mixed-Signal Devices puts itself between the two by offering digitalling synthesized clocks based on CMOS.
 

MSO’s approach is to digitally synthesize clocks, but the DAC technology here is critical.

In contrast to the analog clock chip players, Madisetti said they decided to go down a different path. Rather than stay with PLLs, they approached things from a comms point of view by leveraging DDFS (Direct Digital Frequency Synthesis). DDFS technology has been around for a long time, but not used for high performance applications.

As Madisetti explains, the concept of DDFS is you generate a sine wave digitally, and then you pass it through a high performance digital to analog converter, pass it through a low pass filter, and there you get an output. “That’s all easier said than done,” he said. “The big challenge is this D-A converter has to be really good. People have used this in digital audio, but that was in the kilosamples per second. You need something in the giga samples and it has to be very spectrally pure.”

Building a Better DAC

One of the company’s breakthroughs was designing a DAC which has a spectral efficiency around 1,000 times 60 dB better than state of the art, according to Madisetti. To do this, they leveraged bulk acoustic wave (BAW) technology.

MSO’s approach is to combine BAW, a virtual crystal, a spur-free DAC, and CMOS DSP to create a digital clock.

“We created something called the Virtual Crystal," said Madisetti. “We take the BAW, we have a DAC, which is pretty spur-free, we throw in a crystal, and we have our CMOS DSPs. All of these work together under the umbrella of digital synthesis to create a clock. And we calibrated the BAW from 3,000 ppm down to 1 ppm over the whole temperature range from minus -40 C to +105 C.”

This design is built on 28 nm CMOS technology and the aforementioned patented Virtual Crystal architecture. They have integration-ready footprints and a range of factory-configurable outputs. 

Four New Products

The new products in the timing portfolio include the MS1130 1 GHz and the MS1150 2 GHz oscillator. These devices offer femtosecond-level jitter, ±20 ppm thermal stability, and programmable configuration in compact CMOS packages. While the MS1130 is optimized for high-frequency applications such as 800G networking and AI compute fabrics, the MS1150 is purpose-built for ultra-low jitter system clocks and timing cleanup in complex architectures.

The other two new products are the MS1500 1 GHz and MS1510 2 GHz jitter attenuators. These are precision timing solutions built for high-speed networking and data infrastructure. The devices provide femtosecond-level jitter, exceptional power supply noise rejection, and robust thermal resilience.

The MS1500 supports up to 1 GHz output, well suited for PCIe and Ethernet clock cleanup, while the MS1510 pushes performance to 2 GHz, targeting coherent optics, SerDes links, and advanced AI platforms. The jitter attenuators are designed to simplify clock tree architectures and enable cleaner signal performance across increasingly complex platforms.

A New Approach to Clocks

As processing and I/O continue to push performance barriers, it’s clear that clocking is at risk of becoming a system bottleneck, particularly in demanding applications such as AI data centers. It appears that Mixed-Signal Devices is addressing these demands by taking a new approach. 

“This is a new way of doing clocks, which is essentially digital,” said Madisetti.

“Even though we have a digital to analog converter, it's a very digital-like architecture. Most of the secret sauce is in all the DSP that controls it.”

All images used courtesy of Mixed-Signal Devices.