Diodes Incorporated

Spread-Spectrum Crystal Oscillator (SSXO)

SSXO uses proprietary PLL and Spread-Spectrum Clock Generator (SSCG) technology to synthesize from and modulate the frequency of the input crystal. Measured radiated energy at the fundamental and harmonic frequencies are reduced to comply with Electro Magnetic Compliance (EMC) requirement. The internal factory setting function enables flexible selection of output frequency, modulation rate and spread ratios.


Related Links   

  • FCP Search Tool:  The Frequency Control Product (FCP) search tool lets you find the right products and datasheets for Quartz Crystal (XTAL) Resonators and Crystal Oscillators (XO).

Spread-Spectrum Crystal Oscillator (SSXO) Details

  • Wide frequency range – 16-67 MHz
  • Flexible spread options – Center Spread, Down Spread
  • Flexible modulation rate option
  • Very low power consumption – 6 mA max for 2.5 V VDD, 10 mA max for 3.3 V VDD
  • Industry standard low profile packages – 3.2 x 2.5 mm, 5.0 x 3.2 mm, 7.0 x 5.0 mm

Applications

  • Multi-function printers
  • Wire and wireless networking devices
  • Media players
  • LCD panel
  • Digital television
  • Video surveilance

Spread-Spectrum Crystal Oscillator (SSXO) FAQs

Define Stability?

Parameter used to define the maximum deviation of the actual frequency from the specified nominal frequency over changes in operating conditions. Oscillator stability is usually rated as inclusive of temperature, load, initial calibration, supply, and aging effects.

Is there a replacement for an obsolete part?

Not all obsolete parts will have a direct replacement. However, we recommended that you contact your regional sales office.

What are the types of jitter?

There are several types of jitter, but the main ones are: cycle-to-cycle jitter, period jitter, half period jitter, and peak-to-peak jitter. Jitter terminology can be found in AB36: Jitter Measurement Techniques at Application Brief No. 36 or Application Note No. 27.

What is cycle-to-cycle jitter?

Cycle-to-cycle jitter is the difference in the clock's period between two consecutive cycles and is expressed in units of + pico-seconds. This is because it can be either leading or lagging from the ideal output waveform.

What is half-period jitter?

Half-Period Jitter is the measure of maximum change in a clock's output transition from its ideal position during one-half period. It is measured as: tjit(half-period) = thalf-period n – 1/2 ƒo, where ƒo is the frequency of the input signal.

What is Jitter?

Measurement of the deviation of a clock period from its ideal position as calculated with respect to the average operating frequency under a fixed set of operating conditions.

What is PPM?

Part per million is used to measure the deviation of the output signal (+/-20 ppM = +/-0.002%).

What is the lead finish for Pericom products? What about lead-free?

All Pericom's products that are not lead-free are composed of 85% Sn and 15% Pb. For lead-free products, they are composed of 100% matte Sn. Lead-free products are marked and ordered with the letter "E" suffix at the end of the part number.

What is XO or SO?

A crystal (or SAW) oscillator outputs a precise fixed-frequency clock signal at a specified nominal value, used for data and processor timing.

Where can I find Mean Time Before Failure (MTBF) or Failures In Time (FIT) values for Pericom products?

FIT and MTBF data can be found at Pericom's Quality webpage.

Where can I find the information on your Pb-free and "Green" packaging?

Lead (Pb)-Free and Green information can be found on individual datasheets or Pb-Free & Green Page.

Why is the marking on the FCT devices different from the datasheet?

Sometimes the speed grades and the package nomenclature for our FCT devices may be swapped around. Full explanation for nomenclature information can be found under Packaging Support Documentation.