Record Setting Silicon Resonator Reaches 4.51 GHz

bibekpaudel brings news that researchers from Cornell University have developed a very small silicon microresonator that vibrates at the highest frequency ever recorded for such a device: 4.51 GHz. Typical quartz-crystal oscillators, commonly used in electronics as clock signals, are about a millimeter wide and operate in the KHz - MHz range. The newly developed microresonator measures 8.5 micrometers long and 40 micrometers wide, making it ideal for use in smaller circuits and microprocessing. Quoting: "One of the advantages of silicon microresonators is that they can be integrated directly into microchips using conventional manufacturing techniques, making them cheaper to produce and easier to fabricate small. Also, multiple resonators of different frequencies could be put on the same chip, says Ville Kaajakari, an assistant professor of electrical engineering at Louisiana Tech University. In a cell phone, for example, high-frequency resonators could filter out interference from other sources of radio signals."

Comments

this will benefit lower freq apps too

[v1]

Something I'm surprised the article did not point out is its applications in lower frequency use. If you want to create a stable clock that counts seconds, you don't make an oscillator at 1hz (one beat per second), you create one that does much more, say 1000hz, and then divide that by 1000. So if you are off by a few cycles it doesn't matter much. The greater this multiplication the better. So a fairly stable 4.5ghz reference could be divided down to make an extremely accurate and stable say, 500mhz signal.

Re:this will benefit lower freq apps too

[Gibbs-Duhem]

The only thing that matters is the accuracy. If your 4.5gHz clock is accurate to 1ppm, it will be off by 4500 counts every second, which happens to be equal to a drift of 1 millionth of a second every second. If your 1Hz clock is accurate to 1ppm, surprise, it will also drift by 1 millionth of a second every second.

Not to say you would use a 1Hz clock for a second counter, but this is more because it's convenient to not have to wait around in software for a clock edge to start calculations, and because the accuracy goes up when you get to real resonators (which don't exist so much at 1Hz).

Re:this will benefit lower freq apps too

[Original Replica]

Why is it necessary to count to 4.5 billion for a 500mhz clock? Every nine ticks of the 4.5ghz clock give one click to the 500mhz clock. Counting to nine is easy.