A CMOS 1.8 GHz low-phase-noise voltage-controlled oscillator with prescaler

The two HF components for a full CMOS 1.8 GHz frequency synthesizing PLL, the VCO and prescaler, are realized. The low-phase-noise oscillator employs bondwires for the high-quality on-chip inductor. A special LC tank design enables an even further reduction of the phase noise. The prescaler uses an enhanced ECL-like CMOS D-flipflop and has a fixed division ratio of 128. The VCO and prescaler are integrated in a standard 0.7 /spl mu/m CMOS process.