The MS1130 and MS1150 oscillators from Mixed-Signal Devices utilize digital architecture to generate clock signals with low noise and low jitter.
Mixed Signal Devices (MSD) has unveiled two clock generators tailored for synchronizing signals in data centers, telecom networks, and other digital communication systems. The MS1130 (10 MHz to 1 GHz) and MS1150 (20 MHz to 2 GHz) employ a digital architecture that, according to MSD’s Avi Madisetti, produces clocks with minimal noise. As data rates escalate, combating noise and jitter becomes increasingly challenging.
The block diagram illustrates how the devices utilize a digital sine generator, DAC, bulk acoustic wave (BAW) resonator, and a low-pass filter (LPF) to generate an output. MSD refers to the BAW resonator as a “virtual crystal.” The digital sine generator generates a 16-bit word for each sample point of the waveform. The DAC converts each digital word into an analog voltage, where the virtual crystal generates timestamps. The LPF refines the signal by eliminating high-frequency content to yield the final output.
During a discussion with EE World, Madisetti clarified that the DAC generates analog voltage levels without generating the typical spurs seen in DACs. This, he mentioned, is how the oscillators achieve low noise levels. Refer to the provided links to access datasheets for more information. The devices incorporate fully autonomous DSP algorithms that operate in the background to continuously monitor the device, ensuring consistent performance across process, voltage, and temperature variations.
When addressing high-speed digital communication buses, jitter becomes crucial. The MS1130 boasts RMS phase jitter of 32 fs, while the MS1150 features 30 fs of jitter when tested at 312.5 MHz. The temperature range spans from -40°C to 85°C, with an optional extended range up to 105°C available.
Presently, the output frequency is factory-set, although Madisetti mentioned that upcoming devices will be field programmable via an I2C interface.
Packaged in 2.5 mm × 2.0 mm 6-pin land grid array (LGA) packages, both the MS1130 and MS1150 are accessible in sample quantities for engineering assessment.
Filed Under: IMS, Oscillators, Timing, Timing ICs
