Silicon clock oscillators are proving equivalent in performance, if not superior, to ceramic resonators. Simpler to use and more reliable, they also supply a faster startup and are robust, while providing the same frequency tolerance operating between -55°C and 150°C.
This has been the case since 1995, when Micro Oscillator Inc. introduced the first silicon oscillator chip. It was used as an accurate frequency source for military munitions applications under conditions of shock and vibration, which often leave ceramic and quartz resonators nonfunctional or destroyed.
Ceramic resonators have another disadvantage. They need to be matched to specific driver IC types and manufacturers. Subsequently, resonators are still subject to startup failure as well as jumping to the wrong operating frequency.
To date, a higher price and a lack of secondary sources, combined with nonfamiliarity, have hampered high-volume commercial use of silicon clock oscillators. Once these issues are resolved, silicon clock oscillators will swiftly replace the now outdated ceramic resonators.
Silicon clock oscillators are forming a new market based on their unique ability to be packaged or integrated directly into other silicon IC solutions. The user has the advantage of a total solution in one package, with the significant benefit of reduced product size. The oscillator can be integrated on one IC die, or combined with other dies, in one package. The standalone market will continue to exist because it offers the most flexibility.
Future developments will divide the silicon clock oscillator's market into two segments. The first market will focus on price reduction competitive to ceramic resonators. The second market will concentrate on applications with higher profit margins, such as USB and automotive bus controllers. These applications require frequency tolerances that can only now be met by more expensive quartz crystals.
Furthermore, silicon clock oscillators will have value-added features, such as spread-spectrum capability, that aren't readily incorporated with ceramic resonator technology. Ceramic resonator technology is mature and has reached its technological limit, while silicon clock oscillator technology has only just begun.
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