Quartz-Crystal and SAW Oscillators

Quartz-crystal Oscillators

FemtoClock® NG 5 x 7 mm devices are clock frequency sources that provide frequencies from 15.48 MHz to 1300 MHz. The devices use IDT’s 4th generation fractional-feedback PLL technology and integrate the crystal within the package. Each device features a set of up to four user defined frequencies that are pre-programmed from the factory. An additional I2C programming interface allows access to internal PLL registers for reconfiguring the output frequency. The VCXO devices also allow configuration of the absolute pull-range (APR) from ±7.5 to ±757.5 ppm. Compatible with the standard 6-pin 5 x 7 mm ceramic package, these devices are an ideal alternative to classic oscillators, SO, VCXOs and VCSOs, with the additional benefit of a 4-pin interface for output frequency programming. The devices use standard outputs such as differential LVPECL, LVDS and single ended LVCMOS. These devices can be ordered with integrated crystals with an accuracy of ±20, ±50 or ±100 ppm.

FemtoClock NG devices are the choice of the advanced system designer seeking a clock source with top performance and unmatched flexibility in a standard oscillator footprint. Using IDT’s new 4th generation fractional feedback synthesizer architecture, the devices offer low phase-noise characteristics (<0.5 ps RMS) that are required for reference clocks in applications that cannot compromise in signal quality, conversion error and bit error rate. The linearity of the VCXO outperforms most existing tunable oscillators.

Programmable FemtoClock NG Oscillators

FemtoClock NG devices can be used in standard 5 x 7 mm oscillator footprints. The phase noise performance of the FemtoClock NG 5 x 7 mm family enables their use as reference clocks for phase-noise sensitive applications. They are ideal for clock applications where low phase noise reference clocks improve transmission distance or reduce bit error rates and conversion errors. Additional examples of application uses can be found in wireless infrasructure radio and base-band processing units, high-speed SerDes clocking (for instance S-RIO 1.3 and 2.1), PCI Express® Generation 1, 2 and 3, various Ethernet interfaces (Gigabit Ethernet, XAUI and 10 Gbit Ethernet), optical interfaces in SDH/SONET applications (OC-12, OC- 48 and OC-192) and in driving DAC/ADC devices in instrumentation applications.

SAW Oscillators

IDT offers a family of variable frequency voltage-controlled surface acoustic wave (SAW) oscillators (VCSO). They are available in 5 x 7 mm hermetically sealed ceramic surface mount packages that incorporate the oscillator IC and the SAW delay in the package. Standard output frequencies, from 100 MHz to 900 MHz, are readily available. The high-Q quartz SAW delay lines that control the frequency of the VCSOs yield low phase noise and jitter, as well as an extremely stable frequency, over the operating temperature range. The VCSOs are well-suited for high performance PLL circuits such as jitter attenuation and frequency translation, as well as other timing applications in telecom and optical networking systems. IDT Dual Frequency VCSOs are an ideal source for low-jitter clock generation. An integrated SAW (surface acoustic wave) delay line implements the high-Q VCO (voltage controlled oscillator) function, which results in low output phase noise and very low jitter.

Video: 5x7 Clock Overview