Design and printed circuit board level implementation of a narrow band LC VCO

A Voltage Controlled Oscillator (VCO) using a 0.6 &mgr;m CMOS technology has been designed and fabricated. The design's tuning range is from 390 MHz to 410 MHz, with the centre frequency being 400 MHz. The oscillator is powered by a 2.5 volt power supply. The controlling voltage varies from 0.87 to 1.6 volts. Simulation of the LC VCO was carried out in Advanced Design System (ADS). For the printed circuit board level implementation, the layout was first performed using the Orcad program, and then its image was transferred on to a printed circuit board. The device footprints were incorporated in the circuit board layout. The dimension of the completed board was 1.5 x 1.5 inches. The frequency of oscillations was found to vary from 940 kHz to 2.2 MHz while the phase noise at center frequency of 1.4 MHz was found to be -78 dBc/Hz at 10 kHz offset.