SiTime, Silicon MEMS Oscillators and Clock Generators

SiTime’s family of SiT912x differential oscillators provide a high performance solution with only 500 femtoseconds of RMS phase jitter measured from 12 kHz to 20 MHz.

The excellent frequency stability of this family provides better timing margin to enhance system stability and robustness. The SiT912x family is ideal for 10GbE and other high-speed serial applications such as:

• Multi-port Ethernet switches
• Fiber to the Home (FTTH) equipment such as optical line terminals (OLT) and optical network units (ONUs)
• Broadband customer premise equipment (CPE)
• RAID controllers
• Host bus adapters (HBA)
• Solid state drives (SSD)

In certain network configurations or board designs, packet losses can be eliminated by increasing the reference clock by 25 PPM or 50 PPM (this technique is also known as PLUS PPM CLOCKING). This technique involves using custom frequencies such as 156.25391 MHz to drive 10Gb Ethernet chipsets.

Such customized frequencies are available from quartz crystal suppliers with 12-16 weeks lead time, and this is typically too long for designers to wait. SiT912x devices are available with extremely short lead-times and in industry-standard packages, enabling quick, easy and cost-effective replacement of quartz-based solutions.

For standard frequencies such as 156.25 MHz and 161.1358 MHz, SiTime offers the SiT9120 oscillator and for any customized frequency >220 MHz (with 6 decimal places of accuracy), SiTime offers the SiT9122 oscillator. Both devices offer the following features.

• Any frequency stability from ±10 PPM to ±50 PPM
• -20 ºC to 70 ºC or -40 ºC to 85 ºC operating temperature range
• 2.5V or 3.3 V operations