Precision timing devices target telecoms

SiTime, a MEMS and analogue semiconductor company, has introduced the Elite Platform, which comprises of Super-TCXOs (temperature compensated oscillators) and oscillators.

These precision devices have been developed to address long-standing timing problems associated with telecommunications and networking equipment and that are caused by denser networks and deployments in ‘uncontrolled’ environments.

“Precision timing components in these systems must now operate in the presence of high temperature, thermal shock, vibration and unpredictable airflow. Service providers are questioning if quartz technology is up to this challenge,” said Rajesh Vashist, CEO at SiTime. “Customers have enthusiastically validated SiTime’s MEMS-based Elite Platform, and we believe it will transform the $1.5 billion telecommunications and networking timing market.”

Elite timing solutions are based on a DualMEMS architecture with TurboCompensation and comprises of three key elements:

• Proven TempFlat MEMS that eliminates activity dips and enables 30 times better vibration immunity than quartz

• DualMEMS temperature sensing with 100% accurate thermal coupling that enables 40 times faster temperature tracking, which ensures the best performance under airflow and rapid temperature changes

• Highly integrated mixed-signal circuits with on-chip regulators, a TDC (temperature to digital converter) and a low-noise PLL that deliver 5 times better immunity to power-supply noise, 30 uK temperature resolution that is 10 times better than quartz, and support for any frequency between 1 and 700 MHz

The Elite Platform comprises four new product families with a wide range of frequencies and features. All Elite solutions offer 0.1 ppb/g vibration immunity and do not have activity dips or micro-jumps.

Stratum 3 precision Super-TCXOs for communications and cloud infrastructure equipment:

• ±100 ppb frequency stability over -40°C to +105°C, the widest operating temperature available with any TCXO

• 1 to 5 ppb/°C frequency slope (ΔF/ΔT) at an extremely fast temperature ramp rate of 10°C/minute, a performance level that is unique among timing devices

• 3e-11 Allan deviation (ADEV) at 10 second averaging time, 10 times better than typical quartz TCXOs

• 0.2 ps/mV power supply noise rejection (PSNR), eliminates dedicated system LDO

• Optional I2C/SPI frequency tuning, eliminates external DAC

Super-TCXOs for GNSS, industrial and automotive applications:

• ±0.5 ppm frequency stability over -40°C to +105°C

Ultra-low jitter differential oscillators:

• 0.23 ps integrated RMS phase jitter (12 kHz to 20 MHz)

• 0.1 ps integrated RMS phase jitter under Ethernet mask for 10G/40G/100G

• ±10 ppm frequency stability over -40°C to +95°C, enabling better system reliability

High-temperature high-reliability differential VCXOs:

• Up to +95°C with excellent phase noise

• Wide pull range from ±25 ppm to ±3600 ppm

• 0.1% frequency tuning linearity under all conditions, 50 times better than quartz

Engineering samples of the Elite-based ultra-low jitter differential oscillators and high-temperature VCXOs are now available to qualified customers and samples of Elite-based Super-TCXOs are expected to be available in the first half of 2017.

Neil Tyler