CIE Components in Electronics
Exar Corporation has made an addition to its range of telecommunications timing products with a new family of Universal Clocks. The XR811xx series offers a wide range of output frequencies from 10MHz to 1.5GHz, with ultra-low phase noise jitter of less than 200fs.
Designed for communications, audio/video and industrial applications, the QFN-10 and TSSOP-8 packaged devices are footprint compatible with industry standard synthesizers, providing a superior performance second source option.
The design of the XR811xx synthesizers utilizes a highly flexible delta-sigma modulator and a very wide-ranging VCO in a PLL block that has been optimized to be extremely power efficient. With a core current consumption of just 20mA, these parts dissipate 60% less power than equivalent competitive devices, providing a very compelling power efficiency benefit to system designers. The PLL can operate from either an input system clock or a crystal and incorporates both an integer divider and a high-resolution (<1Hz) fractional divider for increased flexibility to generate any clock frequency.
In addition up to four different frequency multiplier settings can be stored allowing for different application configurations providing BOM savings compared to multiple synthesizers. The XR811xx family also offers a choice of LVCMOS, LVDS or LVPECL output drivers.
Exar’s Universal Clock devices deliver extremely low, sub-200fs, output phase noise jitter as integrated over a PLL loop bandwidth of 1.875MHz – 20MHz. This spans the requirements of most WAN and LAN systems and supports communications standards including: 10GHz Ethernet, 2.5GHz and 10GHz SONET/SDH/OTN, xDSL and PCIe, as well as many other synchronized clock system applications.
