125-MHz fully integrated fixed frequency low-jitter crystal oscillator clock generator

The CDC421Axxx is a high-performance, low-phase-noise clock generator. It has an integrated low-noise, LC-based voltage-controlled oscillator (VCO) that operates within the 1.75 GHz to 2.35 GHz frequency range. It has an integrated crystal oscillator that operates in conjunction with an external AT-cut crystal to produce a stable frequency reference for a phase-locked loop (PLL)-based frequency synthesizer. The output frequency (fOUT) is proportional to the frequency of the input crystal (fXTAL).

The device operates in 3.3-V supply environment and is characterized for operation from -40°C to +85°C. The CDC421Axxx is available in a QFN-24 4-mm × 4-mm package.

The CDC421Axxx differs from the CDC421xxx in the following ways:

* Device Startup The CDC421Axxx has an improved startup circuit to enable correct operation for all power-supply ramp times.