SAW Oscillator For Low Jitter PLLs

Produced by Vectron, the VS720 is footprint-compatible with the existing VS700 SAW oscillator, making it a plug-in replacement in designs for PLL (phase lock loop) applications that require lower VCXO gain, improved holdover temperature stability and/or initial accuracy.

The latest design employs bulk acoustic wave (BAW) and surface acoustic wave (SAW) filters fabricated in Vectron’s US-based Hudson, NH and European, Neuchatel, Switzerland factories respectively. These are combined with a dedicated custom ASIC design to produce a very low RMS jitter performance of less than 0.25ps RMS across the 12kHz to 20MHz range (622.08MHz output frequency). Output frequencies for the VS720 range from 300MHz to 800MHz, compared to 500 to 800MHz for the VS700, which is a first for a device this size.

The SAW-based oscillator features tight frequency stability over a wide operating temperature range. Specifications include temperature stability of ±20ppm typical and minimum APR of ±50ppm over the –40oC to +85oC temperature range. Initial accuracy is ± 25ppm typical @25oC for Vc of 1.65V. Linear VXCO gain is approximately 75ppm/V. Additional features include 3.3V operation and an enable/disable function on pin 2.

The VS720 is housed in a standard 5mm x 7.5mm hermetically sealed leadless, surface mount package and complies with RoHS requirements for lead-free products.

Last year, Vectron acquired Corning Frequency Control (CFC), a leading supplier of quartz crystals, oscillators and filters designed for the communications, test instrumentation, position location, automotive and military/aerospace markets.