Lowest phase noise frequency synthesizer uses multicore VCO

January 23, 2013 // By Nick Flaherty
Texas Instruments has introduced a wideband frequency synthesizer with integrated voltage-controlled oscillator (VCO) that delivers the industry’s lowest phase noise.

The LMX2581 combines the capability to drive highest system performance along with the flexibility of a wideband frequency synthesizer that outputs 50 to 3760 MHz. It allows designers to use one frequency synthesizer to support a variety of demanding applications in wireless infrastructure, radar, medical imaging, defense and aerospace, and test and measurement.
In addition, the LMX2581 improves total link power efficiency and communication channel capacity when combined with high-speed analog signal chain devices from TI such as the LMK04828 or LMK04800 clock jitter cleaner.
The LMX2581 improves RF sensitivity with a phase detector frequency of 200 MHz and ultra-low PLL normalized phase noise of -229 dBc/Hz provides a precision local oscillator to an RF front end for better receiver sensitivity. The multi-core VCO provides maximum flexibility as the integrated VCOs allow the device to output frequencies from 50 MHz to 3760 MHz, eliminating the multiple VCO/PLL combinations typically required to support a broad range of applications. The LMX2581 also gives designers the option to bypass its internal multi-core VCO in favor of an external VCO. A delta-sigma PLL engine with 200-MHz phase detector frequency also boosts spurious performance.
The LMX2581EVAL evaluation module can be purchased today for US$175. The synthesizer’s companion Clock Design Tool and CodeLoader software help speed system design by aiding engineers with product selection, loop filter design and simulation of timing solutions. Both of these tools and other clock design software are available in the WEBENCH Design Center.
The LMX2581 is available today in a 32-pin, 5-mm x 5-mm QFN package for a suggested retail price of US$7.00 in 1,000-unit quantities.
www.ti.com