Microwaves & RF |
CMOS Clock Approach Breaks Quartz Tradition |
| Abstract: | This technology provides accurate frequency generation entirely in standard CMOS, a task formerly accomplished exclusively with quartz resonators and crystal oscillators. Clock generation generally evokes images of quartz crystals and quartz-crystal oscillators. The technology has existed since before World War II and has provided reliable reference signals in communications systems around the world. If ever a technology could be considered "disruptive," it would be the one that displaced or at least provided an alternative to quartz crystals for this task. As will be shown, that technology exists and is based on the fabrication of reference signal sources entirely with silicon CMOS technology, forming a line of signal generators called CMOS Harmonic Oscillators (CHO™) [read more] |
| Planet Analog January 2007 |
Basics of Selecting the Optimal Frequency Source For an Application -Part 1 & 2 |
| Abstract: | This article analyzes various frequency sources available to the design engineer, from both technical and business perspectives, with the goal of helping select the right frequency source to meet specific system requirements. Because they are by far the most popular, this article will examine quartz-based crystal oscillators in particular, and describe their applications, advantages and disadvantages. Given the rapid growth of consumer electronics, some limitations of quartz crystals have become more pronounced. The article also reviews several recently proposed alternatives to quartz crystals and describes their key properties, such as ceramic resonators and CMOS resonators. [read more] |


