SiTime, Silicon MEMS Oscillators and Clock Generators

SiTime's Solution for 10GbE with Excellent Jitter and High Stability

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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

SiTime’s MEMS Oscillator Solutions for Ethernet Systems BER

Applications

SiTime Device

Device Specification

10 Gigabit Ethernet

SiT9120AI-1D2-33E156.2500000

156.25MHz, 7050 package, 3.3V, ±25 PPM, -40 to 85 C

10 Gigabit Ethernet

SiT9121AI-1D2-33E156.253910

156.25MHz w/ 25PPM freq shift, 7050 package, 3.3V, ±25 PPM

1 Gigabit Ethernet or GPON/EPON

SiT9120AI-1C2-33E125.000000

125MHz , LVPECL, 5032 package, 3.3V, ±25 PPM, -40 to 85 C

1 Gigabit Ethernet or GPON/EPON

SiT9121AI-1C2-33E125.003750

125MHz w/ 50PPM freq shift, 5032 package, 3.3V, ±25 PPM

10 Gigabit Ethernet

SiT9122-2D2-25E312.500000

312.5MHz, LVDS, 7050 package, 2.5V, ±25 PPM

10 Gigabit Ethernet

SiT9122-2D2-25E625.000000

625MHz, LVPECL, 7050 package, 3.3V, ±25 PPM

PCI-E

SiT9102AI-433N33E100.000000

100 MHz, HCSL, 5032 package, 3.3V, ±50 PPM

System Processor

SiT8103AI-83-33E-66.667000

66.667MHz, 7050 package, 3,3V, ±50PPM

 

 

SiTime products also offer the following options for customization

  • Any frequency between 1 to 625 MHz with 6 decimal places of accuracy
  • Operation at 2.5V or 3.3V configurable
  • 5032 or 7050 packages
  • LVPECL, LVDS, or HCSL

Roll mouse over colored blocks for more information.

10-gbe-block-diagram

1. Frequently used device:

SiT9120AI-1D2-33E156.250000  MHz 
±25 PPM stability
3.3V voltage supply voltage

Click here for other possible SiT8208 configurations

2. Frequently used device:

SiT8209AI-32-33E-133.33 MHz
±25 PPM stability
3.3V voltage supply voltage

Click here for other possible SiT8209 configurations

3. Frequently used device:

SiT8103AI-83-33E-66.667000 MHz
50 PPM stability
3.3V voltage supply voltage

Click here for other possible SiT8103 configurations

4. Frequently used device:

SiT8209AI-32-33E-156.253910 MHz 
50 PPM shift from standard 156.25 MHz reference
±25 PPM stability
3.3V voltage supply voltage

Click here for other possible SiT8209 configurations

5. Frequently used device:

SiT8209AI-32-33E-125.000325 MHz 
25 PPM shift from standard 125 MHz reference
±25 PPM stability
3.3V voltage supply voltage

Click here for other possible SiT8209 configurations

6. Frequently used device:

SiT8209AI-32-33E-125.000325 MHz 
25 PPM shift from standard 125 MHz reference
±25 PPM stability
3.3V voltage supply voltage

Click here for other possible SiT8209 configurations

7. Frequently used device:

SiT8209AI-32-33E-125.000325 MHz 
25 PPM shift from standard 125 MHz reference
±25 PPM stability
3.3V voltage supply voltage

Click here for other possible SiT8209 configurations

8. Frequently used device:

SiT8209AI-32-33E-125.000325 MHz 
25 PPM shift from standard 125 MHz reference
±25 PPM stability
3.3V voltage supply voltage

Click here for other possible SiT8209 configurations

Depending on the design, some blocks may not be necessary.

SiTime products also offer the following options for customization

  • Any frequency between 1 to 625 MHz with 6 decimal places of accuracy
  • SiT9120 for standard frequencies; SiT9121 and SiT9122 for any custom frequency
  • Operation at 2.5V or 3.3V, configurable.
  • 5032 and 7050 packages
  • LVPECL or LVDS signaling
  • ±10, ±25, or ±50 PPM frequency stability

 

 

Design Considerations MEMS Oscillator Features
  • Eliminate network packet loss
  • Configurable frequency skew at ±25 PPM and ±50 PPM of base frequency
  • Meet carrier requirements such as drop-test
  • 50 KG shock resistance
    70 G vibration resistance
  • Same availability of custom frequency devices as standard frequencies
  • 2-4 weeks lead time, best in the industry for any combination of frequency, stability, voltage, package and other factory-programmable features
  • Minimize field failures and costly filed service calls
  • 500 million hour MTBF
  • Enhance system robustness with better timing margin
  • ±10 PPM stability over the entire operating temperature range
    Insensitive to temperature variations